Spitzer Heritage Archive Help

Transcription

1 This document last updated on Wed Apr 10 11:18:22 PDT 2019

2 Table of Contents Quick Start Guide About Spitzer Overview Basic Features and Functions Searches -- The basics of searching History/Tags -- Your search history and tag history Read FITS File Preferences Help Catalogs Download data Searching By... Position (Position Searching in Batch Mode) Abstract Search AORKEY Campaign IRS Enhanced Products Moving Object Moving Object Precovery Observation Date Observer Name Program ID More on Enhanced Products API Search Results Observation (AOR) Level 1 (BCD) Level 2 (PBCD) Filtering Restricting Data in Other Tabs Tagging a search IRS Enhanced Products Super Mosaics Source List Contributed Enhanced Products Orbit Precovery Details Pane Details tab Data tab AOR Footprint tab AOR DoC tab Data Coverage tab Visualization Overview Basic FITS Viewer Image Toolbox Footprints Spectrum Viewer Breaking from Pane 1

3 WCS Alignment Catalogs Catalogs Overview Catalogs from IRSA Your own catalogs from disk Catalog Filters Plotting Catalogs Examples Downloading Data Overview Background Monitor Downloading Script Acknowledgements User Registration Log In Create New Account Forgot name or pw Edit Profile Change Password Update Change Preferences Examples FAQ More Help/Contact Us Privacy Notice 2

4 Spitzer Heritage Archive (SHA) Quick Start Guide: Getting Up and Running FAST Jump down to section for expert Leopard users. (Note that there are also SHA video tutorials, including a quick start and a longer AAS-demo-style overview, available at the IRSA YouTube channel. Look for the playlist that combines all the SHA videos together.) Searching: Many search methods are available. Most people will probably want to search by position, which is the default option. Target names can be automatically resolved into coordinates using NED or Simbad, or you can specify coordinates (which are echoed back to you, under the entry box, to be sure it understands you correctly). Cone searching is the only option at this time. You can also search by strings through all of the abstracts (e.g., obtaining all programs that explicitly studied planetary nebulae with Spitzer), which is a powerful way to get started in the archive. See the section on searching for more information. Hints, Tips, and Term Definitions: An individual Spitzer observation sequence is an AOR, or Astronomical Observation Request. In certain cases (often calibration or sometimes science observations), you may also see an IER, or Instrument Engineering Request. Either one involves many individual frames. The individual data frames that emerge, calibrated, from the Spitzer pipeline are Level 1, or Basic Calibrated Data, or BCDs. The products that come from combining these individual data frames (such as mosaics of individual pointings) are Level 2, or post-bcd, or PBCD data. Also available are Enhanced Products that come from combining AORs or doing post processing (such as synthetic photometry from spectra or source extraction from images). These are very powerful ways to get started on using Spitzer data in your science pretty much straightaway. Enhanced products generated by the Spitzer Science Center (SSC) are returned in a tab separately from the substantial contributed enhanced products that were delivered by the community to the SSC and IRSA (and continue to be delivered to IRSA); these contributed enhanced products can include mosaics, photometry, spectra, and data from telescopes other than Spitzer. See the section on searching enhanced products for more information. You can search for observations by instrument or by wavelength. IRAC, the Infrared Array Camera imaged at 3.6, 4.5, 5.8, and 8 microns. IRS, the Infrared Spectrograph took spectra between 5.2 and 38 microns, and imaged in two bands centered on 16 and 22 microns. MIPS, the Multiband Imaging Photometer for Spitzer imaged at 24, 70, and 160 microns, and took spectra between 52 and 97 microns. Search Results: The search results appear in up to seven tabs: AORs, Level 1, Level 2, IRS Enhanced, Super Mosaics, Source List, and Contributed Products. Each tab provides a different look at the data retrieved by your search. See the section on understanding your search results for more information. Filtering: Filters, either imposed on your initial search or via your results page, can provide a powerful tool for weeding down search results to the observations you want. Visualizing: Visualization is a powerful tool for understanding exactly what each observation did and deciding what data to download. Spitzer Heritage Archive: Quick Start Guide 3

5 Downloading Data: Click on the checkboxes and then click "Prepare Download" to begin packaging your data for download in the background. See the section on the downloading for more information. Program Interface: You can also access the SHA from the command line. For more help, definitions, etc., see the more detailed online help on the left, please see the IRSA Spitzer website, or the site for the ongoing (warm) mission. A set of frequently asked questions (FAQs) is here. Think you've found a bug? See the section on bugs. Quick Start for Expert Leopard Users The SHA does in fact do everything Leopard did, just differently. Some things it does much better, and there are lots more features as well. Here is a quick-start guide for Leopard experts. The SHA returns your search results in up to seven tabs -- one for AORs (the most compact view of the observations, and the one most like Leopard), one for Level 2=post-BCDs, one for Level 1=BCDs, one for IRS Enhanced Products (meaning developed here at the SSC), one for Super Mosaics (developed here at the SSC), one for Source list (also from here at the SSC) and one for Contributed Enhanced Products (currently meaning [mostly] Legacy Enhanced Products) results. Not all of these are returned by default -- or even exist -- for every search; you will need to enable some of these tabs based on the search parameters. (More information on searching.) To the right of the search results window pane is a details pane, which is also where you can investigate coverage, individual data frames (real data, not jpegs like Leopard), and play with visualization (like Leopard's visualization features). You can also download catalogs into this window. (More information on visualization.) If you have proprietary data you're trying to retrieve......log in first. Click on "sign in" in the upper right of the window. If you don't yet have an account, set one up and the Spitzer Help Desk (help-at-spitzer.caltech.edu) your account name and program number, and ask for that account to be tied to that program. (More information on user accounts.) Finding all data by program number Search by program and enter the program number. (More information on searching.) Continue with "Downloading data" below. Finding data by PI Search by Observer and enter the name you want. You need to enter your whole name, and when you start typing characters in the box, a dropdown will appear with the viable choices. Have many programs? Add a filter -- Click on "Filters" in the upper right of the "Campaign Search Results" pane. Locate the "Program ID" column. If you have a text box, enter "=" and the program ID you want. If you have a filter icon, click on the filter icon, and select from the list the program ID(s) you want, and apply the filter. Just the AORs from that program will appear. (More information on searching.) Once you find the data you want, continue with "Downloading data" below. Finding data by campaign Many programs in the Warm Era are time series observations, and some investigators may want all the data from a given program that have just been released. To do this: Search by campaign for the most recent campaign. Many AORs will be returned. Once the results appear, apply a filter to the results. Click on "Filters" in the upper right of the "Campaign Search Results" pane. Locate the "Program ID" column. If you have a text box at the top of the column, enter "=" and the program ID you want. If you have a filter icon, click on the filter icon, and select the program ID(s) you want. Apply the filter. Just the AORs from that campaign and that program will appear. (More information on searching.) Continue with "Downloading data" below. Spitzer Heritage Archive: Quick Start Guide 4

6 Downloading all data shown Once the search results are returned (and filtered if applicable), click on the checkbox at the upper left of the Search Results window pane, and the individual checkboxes in each row will automatically all be checked. Then click on "Prepare Download" (immediately above the column of checkboxes). Choose which types of data you wish to download. All the data will be zipped up within the Background Monitor. If you have many zipfiles to download, a download (wget) script is also provided, which can enable automatic downloads of all the zipfiles. (More information on downloading data.) Downloading just some of the data shown Click on the checkbox on the far left of the data you want downloaded. You can do this in any of the tabs that are returned. Then click on "Prepare Download" (immediately above the column of checkboxes). Choose which types of data you wish to download. All the data will be zipped up within the Background Monitor. If you have many zipfiles to download, a wget script is also provided, which can enable automatic downloads of all the zipfiles. (More information on downloading data.) Where is this particular file I've come to know and love? Be sure that you have clicked "include ancillary data" when you package up the data. Almost certainly the file(s) you seek are tagged as secondary (ancillary) files; just packaging up the plain Level 1/2 files will just get you the primary products. Beginning users are more likely to just want the primary products, whereas you, an expert user, may indeed want the secondary products too. Where is Leopard's Popular Products search? This is now folded into the "enhanced products" searches, available from the position search, or (for the IRS enhanced products) in a search exclusive to that product. You can choose to have those results returned from the main position search pane. The "Contributed enhanced product" results include a summary tab of all of the contributed enhanced products that IRSA has ingested that meet your search criteria. The IRS enhanced products search offers several options specific to that data. (More information on searching enhanced products generally, and more information on an IRS Enhanced Product search in particular.) Spitzer Heritage Archive: Quick Start Guide 5

7 About the Spitzer Heritage Archive (SHA) This is the Spitzer Heritage Archive (SHA) interface. It currently provides access to all Spitzer data, those from the Cryogenic and Warm Mission eras; passwords are needed for access to data that are still proprietary. The SHA replaced Leopard as the interface to all Spitzer data in Fall Newest features include moving object precovery search, SED plot for SEIP (Spitzer Enhanced Imaging Products) Source Lists, and better x-y plots for all the catalogs. There are also several changes to the look and feel of the interface concurrent with the rest of the IRSA website upgrades. Please note: the site may be down for regular maintenance, which is typically Thursday mornings, 8-10AM Pacific Time. Quick-start Help Please also see the known bugs list. It includes known major/minor bugs, idiosyncrasies, recommended browsers and platforms, etc. About Spitzer The Spitzer Space Telescope (formerly SIRTF, the Space Infrared Telescope Facility) was launched into an earth-trailing orbit on 25 August Consisting of a 0.85-meter telescope and three science instruments, at the time of its launch, Spitzer was the largest infrared telescope ever launched into space. During the cryogenic mission, the instruments aboard Spitzer (IRAC, IRS and MIPS) obtained images and spectra at wavelengths between 3 and 180 microns, with spatial resolution ranging from 2 arcseconds at the shortest wavelengths to 40 arcseconds at the longest. Spitzer is still currently taking data with IRAC at 3.6 and 4.5 during the Warm Mission Era. More information on Spitzer from the cryogenic mission, and more information on Spitzer's current Warm mission, are both available. IRSA and the Spitzer Heritage Archive utilize technology developed for the Virtual Astronomical Observatory (VAO), funded by the National Science Foundation and the National Aeronautics and Space Administration under Cooperative Agreement AST The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center. Privacy Notice About the Spitzer Heritage Archive 6

8 Spitzer Heritage Archive: Overview The Spitzer Heritage Archive (SHA) is the final repository for all of the data collected by Spitzer. It is also the mechanism by which current users of Warm Spitzer download their data. Note that there are also SHA video tutorials, including a quick start and a longer AAS-demo-style overview, available at the IRSA YouTube channel. Look for the playlist that combines all the SHA videos together. The Spacecraft and Instruments The Spitzer Space Telescope (formerly SIRTF, the Space Infrared Telescope Facility), was launched into an Earth-trailing orbit on 25 August Consisting of a 0.85-meter telescope and three science instruments, at the time of its launch, Spitzer was the largest infrared telescope ever launched into space. The instruments aboard Spitzer (IRAC, IRS and MIPS) obtained images and spectra at wavelengths between 3 and 180 microns, with spatial resolution ranging from 2 arcseconds at the shortest wavelengths to 40 arcseconds at the longest. Spitzer is still currently taking data with IRAC at 3.6 and 4.5 during the Warm Mission Era. More information on Spitzer from the cryogenic mission, and more information on Spitzer's current Warm mission, are both available. Terminology This archive of Spitzer data is called the Spitzer Heritage Archive, or the SHA. An individual Spitzer observation sequence is an AOR, or Astronomical Observation Request. In certain cases (often calibration or sometimes science observations), you may also see an IER, or Instrument Engineering Request. Either one involves many individual frames. The individual data frames that emerge, calibrated, from the Spitzer pipeline are Level 1, or Basic Calibrated Data, or BCDs. The products that come from combining these individual data frames (such as mosaics of individual pointings) are Level 2, or post-bcd, or PBCD data. Enhanced Products come from combining AORs or doing post processing (such as synthetic photometry from spectra or source extraction from images). These can be contributed by the community, or generated by the SSC itself. Searching, Results, and Filters Several search options are provided, which are documented in more detail in the section on searching. Searching by position is the most popular search. The search results appear in up to seven tabs: AORs, Level 1, Level 2, IRS Enhanced (shorthand for "SSC-generated enhanced products for IRS"), Super Mosaics and Source Lists (shorthand for "SSC-generated enhanced products for IRAC and MIPS"), and Contributed Products (shorthand for "Contributed Enhanced Products"). Each tab provides a different look at data retrieved by your search. (See the section on understanding your search results for more information.) Filters, either imposed on your initial search or via your results page, can provide a powerful tool for weeding Spitzer Heritage Archive: Overview 7

9 down search results to the observations you want. For example, you can restrict your search to just one instrument or wavelength range, or you can restrict the entries in the tabs to be just the data products pertaining to one AOR. This same filtering mechanism can be imposed on the entire set of IRS enhanced products. Visualization Powerful visualization tools were important to the original Spitzer observation planning and archive tools (Spot and Leopard), and the descendents of these tools are included in the SHA. FITS images from Spitzer or other bands (or your computer) can be loaded into the viewer. The footprint of the observation can be overlaid on an image of your choice. Individual Level 1 or Level 2 products can be viewed interactively. The coverage map (e.g., how many times a given portion of sky was observed) can be overlaid on a FITS image of your choice. See the visualization section for more on visualization. Downloading Data After deciding what data to download, click on the corresponding checkbox on the left side, and click "Prepare Download" to begin the packaging and data download process -- the download then gets passed to the Background Monitor for packaging. See the section on downloads for more information. Tagging and User Preferences There are tools here to help you re-create a search from before (that you or someone else did), called "tagging," or have the SHA remember you (and give you access to your proprietary data). See the user registration section for more information. Spitzer Heritage Archive: Overview 8

10 Basic Features and Functions in the Spitzer Heritage Archive This section is an overview of the basic features and functions of the Spitzer Heritage Archive (SHA); for an even faster overview, see the Quick-Start Guide. For more detailed information on any of these topics, see the more detailed online help on the left. Note that there are also SHA video tutorials, including a quick start and a longer AAS-demo-style overview, available at the IRSA YouTube channel. Look for the playlist that combines all the SHA videos together. The contents of this file follow the menu options (e.g., basically the blue tabs across the top, under the IRSA menu) and major features of the tool in the order in which you might encounter them. Contents of page/chapter: +Spitzer Searches -- The basics of searching +History/Tags -- Your search history and tag history +Read FITS file -- Reading in FITS files +Preferences -- Setting and using your preferences +Help -- Getting more help +Catalogs -- Retrieving and using catalogs +Downloads -- Downloading data and the Background Monitor For an introduction to terminology, please see this summary in the overview section. Spitzer Searches -- The basics of searching Searching the archive is straightforward, and a wide variety of options are available on the left hand side of the search window. The search window can be retrieved after a search by clicking on the blue "Spitzer Searches" tab near the top. The position search is the most commonly used search, and appears by default. Target names can be automatically resolved into coordinates using NED or Simbad, or you can specify coordinates, and you specify the search radius. There are many more search options, described in detail on the section on searching. Spitzer observations can cover large areas or, by design, multiple targets. If you are interested in just portions of the larger observation, you can choose to have just individual data products returned -- e.g., just the observations that went into the portion of the sky for which you searched -- or you can return the products for the whole AOR. You can refine your search for observations by instrument or by wavelength. The search results appear in up to seven tabs: AORs, Level 1 (BCD), Level 2 (PBCD), IRS Enhanced Products, Super Mosaics, Source Lists and Contributed Enhanced Products. Each tab provides a different look at the data retrieved by your search. (See the section on understanding your search results for more information.) You may wish to impose additional filters on your search results; see the section on filtering for more information on filtering. Spitzer Heritage Archive: Basic Features and Functions 9

11 The tabs on the far right of the SHA results page aid in visualizing exactly what data have been retrieved. You can examine individual data frames, or see what parts of the sky are covered by the retrieved AORs. See the section on the Details pane for more information on what is in each tab, and the section on visualization for more information on the options within the visualization tabs. You can also search all of the SSC-developed Enhanced Products or the Contributed Enhanced Products returned to the SSC and IRSA (largely contributed by the Legacy teams). Each team delivered different products, ranging from images, catalogs, and spectra to images beyond the Spitzer bands. See the enhanced products discussion in the searching section for more information. After deciding what data to download, click the checkboxes on the far left of each row to pick specific data files to download, and then click "Prepare Download" to begin the packaging and downloading process. A pop-up window will appear in order to define exactly what kinds of data you would like to have packaged up. Clicking OK initializes this process. The Background Monitor appears as a link in the upper right of your window to keep track of the data download. A pop-up window can be called up by clicking the "Background Monitor" link. You can watch your data being packaged, and when the data are available for download, it will update that window, providing a link (or more than one link) for downloading the packaged data. (More on data downloads.) Important note: don't log in while it is preparing a download! If you log in during a download, as far as the system is concerned, you have changed identities (from 'anonymous' to 'jones', say), and as a result it does not complete preparing the download. History/Tags -- Your search history and tag history The History/Tags menu option gives you access to your own search history and tag history. By default, it comes up with the Search History tab in the foreground; to access the Tag History, just click on the "Tags" tab. Your Search History All of the searches that you do for a given session with the archive are remembered in the search history panel. A high-level summary of the search is also listed -- what kind of search it was, what parameters you used, and the number of AORs or IERs that it returned. You can resubmit the search (see buttons at top left of the search history tab), remove the search from your history, or save the search as a favorite search to which you can return at a later time/date. (However, you do need to be logged in when you save the search -- more on user registration.) Tags and Your Tagging History Many of the papers published on Spitzer data include a list of all the individual AORKEYs (the integer number corresponding uniquely to each AOR) used for data discussed in that paper. This provides an easy way for readers to retrieve the data from the Spitzer archive, and links can be made from ADS directly back to the SHA. However, many papers use many AORs. Data tagging allows you to customize the data set you use so that the link back from ADS (or embedded in your paper itself) refers to a single unique identifier that corresponds to all your data. (That is, a single identifier, as opposed to a potentially long list of AORKEYs.) Once you have established a search that you like, you can click on the "Tag It" icon in the top right of Spitzer Heritage Archive: Basic Features and Functions 10

12 the search results tabs. It will then ask for a nickname, and then return the tag name for insertion into your paper as well as a direct URL you can distribute. Once you have tagged a search, it appears in the "Tags" tab. Read FITS file -- Reading in FITS files Powerful visualization tools were important to the original Spitzer observation planning and archive tools (Spot and Leopard), and the descendents of these tools are included in the SHA. These tools can be used to investigate images of any sort, from your disk or from a variety of online resources, at IRSA or another website. Selecting the "Read FITS File" option from the blue tabs on top of the SHA window results in a large visualization window, into which you can load images from a variety of sources. A pop-up window appears with the available image options. Please see the Visualization section for much more information about the visualization environment, specifically what the icons mean. (Hovering with your mouse over an icon will also reveal a "tool tip" to help figure out what each icon does.) Preferences -- Setting and using your preferences The preferences tab provides a few ways to customize your experience. The window that appears when you click that option gives you by default a choice of the number of entries that appear in the table by default, allows you to enter your for an notification when data are packaged, and allows you to select the default for distance measurements. Log in before setting these preferences, and they will be preserved for you the next time you log in. Getting Help The "SHA Help" blue tab leads you into this online help, as does "Spitzer Help" from under the "Help" in the IRSA menu on the top of the SHA page. You can also download a PDF version of this manual; look at the top of the help window for the "View PDF" link. For an even faster overview, see the Quick-Start Guide. For more detailed information on any of these topics, see the rest of the more detailed online help. Please see the section on more help for more information on getting more help, or contacting us. Catalogs -- Retrieving and using catalogs (Note that this blue tab is only available after you have performed at least one search, e.g., you have something on which to overlay the catalog.) You can choose from any of a wide variety of catalogs to load in preparation for overlaying on your visualized data. First we cover catalogs you can download from IRSA, then we cover using your own catalogs. There is much more information in the catalogs section as well. Spitzer Heritage Archive: Basic Features and Functions 11

13 By clicking on the "Catalog" menu option, a window appears with several options, as follows. The target name is by default the one for the current search/aor with which you are working. If you would like to change the center of the search for purposes of the catalog search, click on "modify target" and enter the new information. All of the same basic parameters as for a position search of the SHA appear. You can then choose catalogs based first on the "project" under which they are housed at IRSA, such as 2MASS, IRAS, Spitzer (includes delivered enhanced product catalogs), MSX, etc. The options under the "category" and the specific clickable catalog on the right change according to the project you have selected. A short description is provided for each of the catalogs, with links for more information. You can also set restrictions on specific columns by clicking on "Set Column Restrictions". A new window will open up with the available column names in the catalog, and you can filter what is returned, with the same basic approach as in filtering your search results in the rest of the SHA. All the restrictions are AND operators. Click on "Search" to initiate the search. NOTE THAT the search may take a long time to return, especially if you have asked for a large catalog, and you may think that nothing has happened, but be patient and eventually it will either spin off to the background monitor, or return a tab. If the catalog search is successful, it will return the results in a tab of its own, in an interface similar to the other data tabs. You can save the catalog to your local disk for future use. If it does spin off to the background monitor, the monitor will dynamically update to reflect its status, and will let you know when the catalog is ready to download or display. Open the background monitor and click on the catalog name to load it into a tab in the SHA. Use large search radii with caution! Be sure you understand how many sources you are likely to retrieve. Searches that retrieve more rows will take longer. Loading your own catalogs By clicking on the blue "Catalogs" tab, you are by default dropped into the interface for searching for new catalogs. However, you can pick another tab from the top left, "Load Catalog", to load your own catalog. Your catalog needs to be in IPAC table format. There is more information in the catalogs section. Downloads - Downloading data and the Background Monitor On any search results page, you can click the checkboxes on the far left of each row to pick specific data files to download, and then click "Prepare Download" (near the top of the column of checkboxes) to begin the packaging (and downloading) process. A pop-up window will appear in order to define exactly what kinds of data you would like to have packaged up. Clicking OK initializes this process. To select all of the data you have displayed, click on the checkbox at the top of the column of checkboxes, and all of the rows are automatically clicked (even those on subsequent pages). Then click "Prepare Download" to initiate the packaging process. Spitzer Heritage Archive: Basic Features and Functions 12

14 The packaging process spins off into the background monitor, which keeps track of its progress and notifys you when the downloads are complete. You can choose to have an sent to you to let you know when things are ready. If you have just a few zip files, you can click to download them, but especially if you have many files, you may want to have the SHA generate a downloading script for you to download them all automatically. Note that you control where the data are saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. For more information, see the section on downloads. Spitzer Heritage Archive: Basic Features and Functions 13

15 Searching the Spitzer Heritage Archive There are many different options for searching the Spitzer Heritage Archive (SHA). Searching by position is the most commonly used option. Contents of page/chapter: +Options Common to Most Searches +Position Search +Abstract Search +AORKEY Search +Campaign Search +IRS Enhanced Products Search +Moving Object Search +Moving Object Precovery +Observation Date Search +Observer Name Search +Program Search +More on Enhanced Products +API Options Common to Most Searches The individual search options are given below, in the same order in which they appear in the search pane. Most of the search panes have the following additional options: Display search results in tabs for... Observation Request (AOR), Level 2 (PBCD), Level 1 (BCD), and sometimes SSC Enhanced Products (IRS), SEIP Super Mosaics, SEIP Source List, and/or Contributed Enhanced Products An individual Spitzer observation sequence is an AOR, or Astronomical Observation Request. Level 2 products are higher-level products, such as mosaics. (These are also called post-bcd, or post-basic Calibrated Data, or PBCD, products.) Level 1 products are the individual calibrated data frames that go into making, e.g., the mosaic (or spectrum). (These are also called BCD, or Basic Calibrated Data, frames.) Enhanced Products come from combining AORs or doing post processing (such as synthetic photometry from spectra or source extraction from images). These can be contributed by the community, or generated by the SSC itself. When you do a search, the results are displayed in tabs, and these tabs correspond to these options. By default, searches return a list of AORs under the "AOR" tab, and a list of Level 2 products under the "Level 2 (PBCD)" tab. You can also choose to access the original BCD frames by selecting the "Level 1 (BCD)" option here, and then the corresponding tab will be returned by your search. Similarly, for most searches, you can choose "SSC Enhanced Products (IRS)", which returns any results in a tab called "IRS Enhanced". These IRS enhanced products were generated on an AOR basis, and as such, most of the searches that can result in a list of AORs can also return IRS enhanced products. However, the other enhanced products ("SEIP Super Mosaics", "SEIP Source List", and "Contributed Enhanced Products") typically combine more than one AOR at a time, and as such, these are really only available from the position search page. Spitzer Heritage Archive: Searching 14

16 NOTE THAT each AOR produces many Level 2 (PBCD) files and many more Level 1 (BCD) files! The number of AORs that may be returned by any given search is going to be much smaller than the number of files that appear on these other tabs. You can "restrict data in other tabs" or apply individual filters to weed down these search results. IMPORTANT NOTES ON ENHANCED PRODUCTS: 1. Any given search may not have any enhanced products to return -- while there are Spitzer observations scattered all over the sky, and while we have developed and had the community return back to us products from observations all over the sky, there is much of the sky not covered by these observations. 2. In order to learn more about the particular values that are returned, how the data were reduced, its strengths and weaknesses, etc., please see the documentation corresponding to the products. The IRS documentation is available as part of the IRS Instrument Handbook at the Spitzer IRSA website. The Spitzer Enhanced Imaging Products (SEIP) Super Mosaic and Source List documentation is also on the IRSA website. Each of the contributions in the Contributed Enhanced Products has its own documentation at the IRSA site (linked from the search results). 3. Many of the 'more options' (see below) obtainable for a position search don't apply to enhanced products of any sort. For example, if you ask the SHA to give you just IRAC observations at a particular position, but also ask it to give you IRS Enhanced Products (which are of course completely independent of any IRAC observations), it will return just IRAC observations in the AOR/Level 1/Level 2 tabs, but the IRS Enhanced Products search is independent of the AOR search, and may still return viable results in that tab. Similarly, if you restrict your search to MIPS results but still ask it to give you IRS Enhanced Products and SEIP Super Mosaics, it will give you IRS and IRAC data, respectively, in those tabs, regardless of the MIPS filter you have imposed (that filter just applies to the AOR/Level 1/Level 2 tabs). More options: filter by Instrument Parameters or Wavelength Range Spitzer has on board three instruments: IRAC, the Infrared Array Camera, which imaged at 3.6, 4.5, 5.8, and 8 microns. IRS, the Infrared Spectrograph, which took spectra between 5.2 and 38 microns, and imaged in two bands centered on 16 and 22 microns. MIPS, the Multiband Imaging Photometer for Spitzer, which imaged at 24, 70, and 160 microns, and took spectra between 52 and 97 microns. By default, the SHA search pane comes up with the "Instrument Parameters" radio button selected. You can ask to have all data from a particular instrument returned (e.g., "All IRAC"). You can also ask to have just data from a particular observing mode returned (e.g., just "IRS Spectral Mapping"). You can also select individual bands, e.g., just 70 and 160 microns). Combine various check boxes to customize your search; go to the Spitzer website at IRSA to learn more about instruments, observing modes, and bandpasses. Alternatively, you can select the Wavelength Range radio button and just enter the minimum and maximum wavelength in which you are interested. Any data in that regime (also meeting your other search criteria) will be returned by the search. After you search the first time, the search pane collapses so the results of your search can be displayed. A summary of the most important parameters of your search is available at the top left. To search again, just click on the triangle near that search summary, or on the blue "Spitzer Searches" tab, to recover the search pane. Position Search This search is the most common search performed on astronomical archives. Enter your central position and Spitzer Heritage Archive: Searching 15

17 cone (circle) radius, then all observations (those meeting all the rest of your entered criteria) intersecting that cone are returned. You may enter a target name, and have either NED-then-Simbad or Simbad-then-NED resolve the target name into coordinates. Alternatively, you may enter coordinates directly. These coordinates can be in decimal degrees or in hh:mm:ss dd:mm:ss format. By default, it assumes you are working in J2000 coordinates; you can also specify galactic, ecliptic, or B1950 coordinates as follows: '46.53, gal' means 46.53, degrees in galactic coordinates '12.7, +4.3 ecl' means 12.7, +4.3 degrees in ecliptic coordinates '19h17m 11d58m b1950' means 19h17m 11d58m in B1950 coordinates As you are completing a valid coordinate entry, the SHA echoes back to you what it thinks you are entering. Look right below the box in which you are typing the coordinates to see it dynamically change. You may enter a search radius; the default is 500 arcseconds. You may enter the radius in arcseconds, arcminutes, or degrees; just change the pulldown option accordingly. Caution: pick your units from the pulldown first, and then enter a number; if you enter a number and then select from the pulldown, it will convert your number from the old units to the new units. There are both upper and lower limits to your search radius; the SHA will tell you if you request something too big or too small. The position search can also be done in "batch mode" from a list of objects given in a file. Please note, the maximum number of targets that can be requested in a batch search is A viable input file can either be an IPAC table file, a relatively simple text file described below, or even a simple comma- or tab-separated value file. For an IPAC table file, you may find the IPAC table file verification service helpful. If doing a regular non-ipac table file search, the file format is: COORD_SYSTEM: Equatorial # Equatorial, Galactic, or Ecliptic - default is Equatorial EQUINOX: J2000 # B1950, J2000, or blank for Galactic - default is J2000 NAME-RESOLVER: NED # NED or Simbad - default is Simbad #Name RA/LON DEC/LAT PM-RA PM-DEC EPOCH "NGC 001" 12h34m23.45s 34d23m56.2s NGC d d NGC h d NGC4444 " " " " m31 legacy " " " " m32 m33 Simbad NGC6946 NGC5194 ngc2992 The SHA parses on spaces, so a space is the delimeter between fields. Therefore, if there is a space in your object name (e.g., "NGC 1001" versus "NGC1001") or position (" " versus 34d23m45.45s"), you need to put quotes around the target name or its position. Spitzer Heritage Archive: Searching 16

18 Having problems making this work? All of the following should be elegantly handled by the SHA, but if you are having problems, it's worth checking these. Check your filename; IPAC table files should end in.tbl, and the plain text search should end in.txt. Double-check your file formatting -- that's the most common error. Make sure there are not lots of extra whitespace (spaces, tabs, etc.) at the ends of lines, particularly the header lines. Check for and remove odd non-ascii characters like curly quotes or Greek letters, and other non-printing special characters (like tabs). Name resolution may fail for some targets with Greek letters or other unusual characters -- provide coordinates for the troublesome names, or remove them. If you are trying an IPAC table file upload that persistently fails, pass it through the the IPAC table file verification service first. If one format (simple text or IPAC table) fails, try the other format (IPAC table or simple text). Apply spatial constraints to AORs or Individual data products This is an additional option for the position searches. An individual Spitzer observation sequence is an AOR, or Astronomical Observation Request. In certain cases -- often calibration or sometimes science observations -- you may also find an IER, or Instrument Engineering Request. Either one involves many individual frames. AORs/IERs can cover large areas or, by design, multiple targets. You can choose to return all AORs/IERs touching your search area, or just the individual data products enclosed within your search area e.g., just the observations that went into the portion of the sky for which you searched. Some products may only exist at the AOR level, e.g., you might get the whole Level 2 mosaic for the whole AOR, but only the Level 1 (BCD) individual data frames for the portion you requested. (The reason you may want the whole AOR, as opposed to just the portion enclosed within your search radius, is that, depending on the nature of the observation and the target, you may want the entire AOR in order to reprocess portions of it. For example, you may want to remove latent instrumental effects, or you may want to use the rest of the AOR to assess the relative error for the region in which you are interested -- e.g., if your dark region of interest is at the end of some scan legs that included a bright region of sky. Please consult the instrument handbook for the relevant instrument in order to assess this for your particular case.) If you do just want to download products within a spatially confined area, be sure you start from the Level 1 (BCD) or Level 2 (PBCD) tabs. Downloads initiated from the AOR search results tab will download the entire selected AOR regardless of spatial constraints. (More information on options found in every search.) Abstract Search You can search on a string through all of the Spitzer program abstracts. You can search on any text you would like, from principal investigator (PI) last names to instrument names to compound terms (such as "brown dwarf"). You can also use simple logic statements, e.g., "star formation -galaxy" means find all instances of the terms "star" and "formation" but not those that also use the word "galaxy." To enforce the appearance of a compound term, e.g., the word "star" next to the word "formation", enclose the term in quotes. (More information on options found in every search.) AORKEY Search An AORKEY is a large integer that uniquely identifies the observation (AOR) within the Spitzer mission. All Level 1 (BCD) and Level 2 (PBCD) files carry with them the fingerprints of this AORKEY (in the filenames, in Spitzer Heritage Archive: Searching 17

19 the directory structure, in the FITS headers...). Specific AORKEYs are often listed in journal articles reporting on Spitzer results. You can retrieve a specific observation by searching on this AORKEY. Note that a single AORKEY corresponds to a single AOR, so if you search on a single AORKEY, you will always get a single AOR in the AOR tab. You can search for many AORKEYs at once by entering a list of them separated by commas. Some observations were obtained with some scheduling constraints, e.g., 'observe this series of 8 AORs in this order within this time window.' In the AORKEY search panel, there is an option to retrieve all the other AORs within the same scheduling constraint. However, note that some time series observations were obtained in the following manner. For a series of observations (a, b, c, d, e), a was tied to b with a particular constraint, b tied to c, c tied to d, and d tied to e. If you search on the AORKEY corresponding to observation b, and ask the SHA to give you all of the AORs constrained to that observation, it does exactly (and only) what you asked it to do -- b is tied to a and c, but not explicitly tied to d or e. So it returns to you observations a, b, and c, and not d or e. (More information on options found in every search.) Campaign Search In some cases, you may wish to browse all of the data taken during a specific campaign, e.g., to investigate bright object artifacts in your data from observations preceeding yours. This feature allows you to do exactly that. A complete list of Spitzer campaigns can be found at the Spitzer website. Note that there are a few different ways to refer to a given Spitzer campaign, and the search only recognizes two of them. For example, IRS campaign 47 was run between 9 Jan 2008 and 23 Jan The formal campaign ID (which works in the search) is IRSX008300, and the search also works with the numerical id 1094 listed as synonymous with this campaign on the Spitzer website. (More information on options found in every search.) IRS Enhanced Products Search The IRS Instrument Team at the SSC has generated IRS enhanced products from low-resolution staring-mode spectra, which include a merged spectrum (all orders), and synthetic photometry at a wide variety of bands. There are no IRS enhanced products for high-resolution spectra or spectral maps. Although IRS data were obtained in a large number of positions all over the sky, any given randomly-selected position is not likely to have any valid IRS products, so these data are not always available. A specialized IRS Enhanced Products search, by default, searches the whole sky. (This is not the case if you select the tick box asking these products to be returned as part of another search, but it is the case if you pick "IRS Enhanced Products" explicitly from the search options.) You can look at all of the meta-data associated with the catalog in a short or long form view (pulldown menu option at the top of the pane), and the rest of the filters you can impose work just like filtering search results. You can impose multiple filters on the available parameters, and then hit the 'search' button on the lower right to return all values meeting your criteria. Spitzer Heritage Archive: Searching 18

20 Note that a plain position search of these data is best accomplished using an explicit "position" search, not from this "IRS Enhanced Products" search pane. In order to learn more about the available parameters on which you can search, the particular values that are returned, how the data were reduced, its strengths and weaknesses, etc., please see the IRS Instrument Handbook, available at the Spitzer IRSA website You can control which columns are displayed, but if you download/save the data, all of the columns are saved. Moving Object Search You can search on the name of a moving target, or the NAIF ID; moving targets are assigned NAIF IDs, which are a unique integer identifier for known Solar System bodies. This search will retrieve data explicitly declared to be observations of these moving targets in the Spitzer database. This means, for example, that observations of a moving target performed as a fixed-target observation of an RA/Dec will not appear, nor will serendipitous observations of a moving target that happens to appear in a fixed-target observation. (More information on options found in every search.) Moving Object Precovery While many moving objects were deliberately observed over the course of the Spitzer mission, many more were serendipitously observed while conducting observations of other things. The Moving Object Precovery search option enables you to detemine if there are deliberate or serendipitous observations of a given object. You need to enter one of the following to enable the archive to calculate an orbit for a given object as a function of time and then look for observations of that object: (1) the object name or NAIF ID (moving targets are assigned NAIF IDs, which are a unique integer identifier for known Solar System bodies); (2) the MPC one-line orbital elements (specification of an object's orbital parameters); or (3) manually input the orbital parameters. You must also specify the time range over which to search for observations. PLEASE NOTE that just asking it to look for objects over the entire Spitzer mission will take a LONG TIME. Use long time baselines with caution! There is an option, after you submit your search, to place the search in the background - this is useful if the search takes a very long time. In any case, it will return results for your search object, both those observed deliberately and those caught serendipitously. Observation Date Search You can search for observations conducted between two dates. The dates must be specified in Universal Time (UT) and be in the format YYYY-MM-DD hh:mm:ss. The maximum date range allowable is small; use big date ranges with caution because thousands of observations can be obtained via this search. (More information on options found in every search.) Spitzer Heritage Archive: Searching 19

21 Observer Name Search You can search by name through all of the principal investigators and technical contacts for all Spitzer programs. Note that there is an auto-complete on this feature, which shows you available suggestions as you type in a string. Note also that searching on any of the instrument PIs (Fazio, Houck, Rieke) or the Instrument Support Team leads (Reach/Carey, Latter/Noriega-Crespo, Armus) will return many programs tied to their guaranteed time (GTO) programs, or calibration programs from early in the mission. To retrieve calibration programs during regular operations, search on "IRS Calibration" or "IRAC Calibration" or "MIPS Calibration." (More information on options found in every search.) Program Search All of the observations that correspond to individual observing programs are grouped under a program identifier (PID). This program identifier can be both a string and a number. Either the string (assigned by the observer) or a number (assigned roughly by the order in which the original proposal was submitted) can be used to retrieve all of the observations that were part of that program. A complete list of all of the Spitzer programs can be found at the Spitzer website. Note that some programs can include literally thousands of AORs, whereas others may be just one or two AORs. Note also that some large science programs may be split over multiple program IDs. (More information on options found in every search.) More on Enhanced Products Enhanced Products come from combining AORs and/or doing post processing (such as synthetic photometry from spectra or source extraction from images). These can be contributed by the community, or generated by the SSC itself. The IRS Instrument Team at the SSC has generated IRS enhanced products from low-resolution staring-mode spectra, which include a merged spectrum (all orders), and synthetic photometry at a wide variety of bands. There are no IRS enhanced products for high-resolution spectra or spectral maps. The SSC has generated enhanced imaging products (SEIP) Super Mosaics and Source Lists from the IRAC and MIPS-24 imaging conducted during the cryogenic mission. These products usually involve more than one AOR. Most (but not all!) of the contributed products come from Legacy Programs. The Legacy Programs were large, coherent science investigations, and the teams explicitly agreed to deliver enhanced products back to the Spitzer Science Center and IRSA. Subsequent to the Legacy program, some large Spitzer programs were called Exploration Science programs, and some of those also delivered products to IRSA. Each team delivered something different -- some just delivered images, some delivered images, catalogs, and spectra, some delivered multi-wavelength resources, extending well beyond the Spitzer bands, some delivered models. All of the products that have been ingested into IRSA are available through this SHA interface. Note that as of this Spitzer Heritage Archive: Searching 20

22 writing, some teams still have pending deliveries, and that IRSA ingestion is not immediate. When a team delivers enhanced data products to IRSA, the data must go through a quality assurance (QA) and ingestion process before being available through IRSA search engines, and this process does not happen instantaneously. As these products become available, they will also be available in this fashion. NOTE THAT, in order to learn more about the particular values that are returned, how the data were reduced, its strengths and weaknesses, etc., please see the documentation corresponding to the products. The IRS documentation is available as part of the IRS Instrument Handbook at the Spitzer IRSA website, the Super Mosaic and Source List documentation is also at the IRSA website, and each of the contributions in the Contributed Enhanced Products has its own documentation at the IRSA site (linked from the search results). The SHA, ultimately, can lead you back to the original AORs for the SSC-generated enhanced products. Look in the headers of the enhanced product files you find to identify the original observations that went into the product, and then search on those observations in the SHA to retrieve the observations. The Super Mosaic and Source List products explicitly include a list of the input AORs. The community-generated ones cannot necessarily do this, since some were generated before the 'final' processing of the BCDs. Since the contributed data products that are being served are so different than the rest of the SHA, the way that the files are listed is also different. Please see the section on search results for more information. IRSA and the Spitzer Heritage Archive utilize technology developed for the Virtual Astronomical Observatory (VAO), funded by the National Science Foundation and the National Aeronautics and Space Administration under Cooperative Agreement AST API Searching by application program interface (API) is covered in another section. Spitzer Heritage Archive: Searching 21

23 Contents of page/chapter: +Overall Introduction +API Introduction +SHA VO Support: SIAP +SHA-specific API: Introduction +SHA-specific API Examples +SHA-specific API Input Parameters +SHA-specific API Output Columns +SHA-specific API Response on error Overall Introduction There are fundamentally two ways to interact with the SHA in an automatic or semi-automatic fashion. The semi-automatic way is to pass a list of sources to the SHA web interface. You can pass a list of up to 1000 sources to the SHA from the search screen. More information on that is in the Searching section. For this, you still need to examine the output of this by hand, but at least you do not have to send targets individually to the server. The more fully automatic way requires you to write some code that conducts a search query and then parses the results to obtain URLs, from which you can download the data. The rest of this section talks about this API, or application programming interface. There are two different ways to query the database. API Introduction An API, or application programming interface, can also be known as a "command-line" interface. It enables programs to interact with the SHA, search for data, and download it. You can write a program that will construct a series of URLs and query our server, resulting in XML files. Then you will need to write code to parse those XML files to obtain the links that you need to download the the data files meeting your search criteria. Please note that it is really easy to inadvertently launch a 'denial-of-service' attack on IRSA's servers if you are not careful. Use this option with caution. Because the API queries result in XML tables, if you click on any of the links below (in this section), your browser may have trouble rendering it, or will render only bits and pieces of the embedded text. You may need to save the contents of the link to a file in order to read what is returned. You may be able to use "View Source" to see the result in more legible format. Note that when you parse the XML file, you will be looking for URLs. To retrieve a URL using wget or curl, you should enclose the URL in quotes. Here are some examples of downloading specific files from the SHA: wget --output-document=postbcd zip " curl --output postbcd zip " There are two different APIs for the SHA. One is complex and powerful, the other is simple, follows a protocol, and is limited. The Virtual Observatory (VO) is a set of data services that all follow a set of standard API rules agreed upon by the International Virtual Observatory Alliance (IVOA). The simpler API follows these rules. Spitzer Heritage Archive: Application Program Interface 22

24 IRSA also has a page about all the program interfaces at IRSA. SHA VO Support: SIAP Currently, the SHA supports Simple Image Access Protocol (SIAP) for Level 1 (BCD) and Level 2 (PBCD) data access. The services support all required parameters listed in the SIAP specification (POS, SIZE, FORMAT) and VERB parameter with two verbosity levels: 1 and 3. With verbosity level 1, only the required and recommended fields are added to the output table. With verbosity level 3, extra fields might be present. They output all the required and some recommended fields. The base URL for these queries is Here are 2 example URLs. These URLs return XML tables that are lists of the metadata that are a part of the VO search. From the descriptions in the XML metadata table, you can figure out what values you need to change in order to do the search you want to do. Simple Image Access for level 1 (BCD) images (DATASET=ivo://irsa.ipac/spitzer.level1) Simple Image Access for level 2 (PBCD) images (DATASET=ivo://irsa.ipac/spitzer.level2) Spectral data are available via this Simple Image Access Protocol rather than the Simple Spectrum Access Protocol. This API will return all the BCD or PBCD data that the Spitzer Science Center produced. They may be images or spectral data. SHA-specific API: Introduction The SHA data can be accessed via an HTTP GET program interface (basically a really long URL) where the request is a set of parameter=value pairs, and what is returned is an IPAC Table containing metadata and URL links to download products with the related ancillary files. This section describes these input parameters and the columns returned. Please note that it is really easy to inadvertently launch something that is functionally equivalent to a 'denial-of-service' attack on IRSA's servers if you are not careful. Please be sure to test your code using only a subset of your desired requests, and add throttle control to your code, e.g., add some 'wait' steps between successive requests. If we notice an undue load on our servers (a real life example is more than 70,000 requests in less than 10 hours), we will block your IP address, so if your requests suddenly stop working, this may be why. Please contact the IRSA Help Desk if this happens. SHA-specific API Examples Search by fixed position applications/spitzer/sha/servlet/dataservice?ra= &dec= &size=0.5&verb=3&dataset=ivo%3a Search by moving target NAIF ID applications/spitzer/sha/servlet/dataservice?naifid= &verb=3&dataset=ivo%3a%2f%2firsa.ipac%2fs Search by program ID applications/spitzer/sha/servlet/dataservice?pid=30080&verb=3&dataset=ivo%3a%2f%2firsa.ipac%2fspitzer.le Search by Astronomical Observation Request ID applications/spitzer/sha/servlet/dataservice?reqkey= &verb=3&dataset=ivo%3a%2f%2firsa.ipac%2 Spitzer Heritage Archive: Application Program Interface 23

25 SHA-specific API Input Parameters The input parameters are entered as standard HTTP parameter=value pairs in HTTP/GET syntax. In this syntax, the parameter name is followed by an equals sign (=) which is then followed by a value. No extra spaces are allowed, and if the value contains any spaces or special characters that might be ambiguous, they have to be encoded formally as in any HTTP or URL reference (more discussion here: As shown above, these pairs are separated from each other by ampersand (&) characters. DATASET VERB RA DEC SIZE NAIFID PID REQKEY Data set. Two sets are supported: ivo://irsa.ipac.spitzer.level1 (BCD data) ivo://irsa.ipac.spitzer.level2 (PBCD data) Verbosity level, controls the number of columns in the output. 1 - selected columns, 3 - all available Search by position: right ascension in degrees Search by position: declination in degrees Search by position: region size in degrees Search by moving target: NAIF ID, which is a unique number allocated to solar system objects (e.g. planets, asteroids, comets, spacecraft) by the NAIF at JPL. Search by program: program ID Search by AOR ID: Astronomical Observation Request ID SHA-specific API Output Columns The output columns in the resultant table describe metadata and include a link to download the requested data product and the important ancillary products related to it. Please note that all output columns are available only when verbosity level is set to 3. Fields returned for verbosity is set to 1 are indicated below. field short description long description reqkey pbcdid AORKEY PBCD ID Spitzer Astronomical Observation Request Number (key) Post Basic Calibrated Data ID (Level 2 product search) returned for VERB=1 no no Spitzer Heritage Archive: Application Program Interface 24

26 bcdid BCD ID Basic Calibrated Data ID (Level 1 product search) no hasaccess accessurl accesswithanc1url Public access Product access reference URL Zip access reference URL "true" if the data is public accessible, "false" if it is proprietary data. The URL to be used to retrieve image or table, "NONE" if product does not have public access The URL to be used to retrieve the image or spectra with important ancillary products (mask, uncertainty, etc.) as a zip archive, "NONE" if product does not have public access modedisplayname Instrument/Mode Instrument/Mode no wavelength Bandpass Bandpass ID yes cra cdec RA (J2000) Dec (J2000) Right Ascension in sexigesimal format HHMMSS J2000, of the FITS image. Example: "2h23m14.3s" Declination in sexagesimal format DDMMSS J2000, of the FITS image. Example: "-12d43m11s" exposuretime Exposure time in seconds Exposure time (Level 1 products only) no primary Primary field If this value is equal to 1, the observation was designed to include the originally specified target. If it is set to 0, the observation was obtained serendipitously of an offset field, and may or may not contain the originally specified target (most often, it does not) filetype Table or Image Table or Image no externalname File name File name yes ptcomment Product description Product description no ra dec crval1 in FITS file crval2 in FITS file Right Ascension in Equatorial J2000 for the center of the FITS image Declination in Equatorial J2000 for the center of the FITS image epoch Epoch Epoch year no equinox Equinox Precessional year associated with the coordinate system begintime Observation start Observation start (Level 2 products only) no endtime Observation end Observation end (Level 2 products only) no scet minwavelength maxwavelength Spacecraft event time: the coordinated universal time on board the spacecraft Min wavelength (microns) Max wavelength (microns) Date and time of data collection event (Level 1 products only) Min wavelength (microns) Max wavelength (microns) filesize File size in bytes File size in bytes yes no yes no no no no yes yes no no no no Spitzer Heritage Archive: Application Program Interface 25

27 campid Campaign ID Instrument campaign ID no ra1 RA of corner 1 dec1 Dec of corner 1 ra2 RA of corner 2 dec2 Dec of corner 2 ra3 RA of corner 3 dec3 Dec of corner 3 ra4 RA of corner 4 dec4 Dec of corner 4 RA position of the lower left image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra1, dec1) = (0.5, 0.5)] DEC position of the lower left image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra1, dec1) = (0.5, 0.5)] RA position of the lower right image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra2, dec2) = (NAXIS , 0.5)] Dec position of the lower right image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra2, dec2) = (NAXIS , 0.5)] RA position of the upper right image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra3, dec3) = (NAXIS , NAXIS )] Dec position of the upper right image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra3, dec3) = (NAXIS , NAXIS )] RA position of the upper left image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra4, dec4) = (0.5, NAXIS )] Dec position of the upper left image corner [pixel space, where first pixel is located at (0.5, 0.5), position (ra4, dec4) = (0.5, NAXIS )] naxis1 naxis1 The size of the image in pixels for dimension 1 yes naxis2 naxis2 The size of the image in pixels for dimension 2 yes cdelt1 cdelt2 crota2 crpix1 crpix2 cdelt1 cdelt2 crota2 crpix1 crpix2 The pixel scale (in degrees on the sky per pixel) at the reference location for dimension 1 The pixel scale (in degrees on the sky per pixel) at the reference location for dimension 2 The rotation angle from the "up" direction to the celestial pole The pixel coordinate of the reference location (can be fractional, in the image center or off the image) for dimension 1 The pixel coordinate of the reference location (can be fractional, in the image center or off the image) for dimension 2 crval1 crval1 [deg] RA at CRPIX1, CRPIX2 yes crval2 crval2 [deg] DEC at CRPIX1, CRPIX2 yes ctype1 ctype1 The coordinate system (first four characters) and WCS map projection (last three characters) for dimension 1 no no no no no no no no yes yes yes yes yes no Spitzer Heritage Archive: Application Program Interface 26

28 ctype2 ctype2 The coordinate system (first four characters) and WCS map projection (last three characters) for dimension 2 no Note that to retrieve a URL using wget or curl, you should enclose the URL in quotes. Here are some examples of downloading specific files from the SHA. wget --output-document=postbcd zip " curl --output postbcd zip " SHA-specific API Response on error If an error occurs when an HTTP request is being processed, an empty IPAC table with a single attribute, named ERROR, will be returned. The error message is a value of this attribute. Spitzer Heritage Archive: Application Program Interface 27

29 Understanding Your Search Results from the Spitzer Heritage Archive This section is an overview of what exactly is returned by a Spitzer Heritage Archive (SHA) search. After a general description of some common options, including how to download data, the individual tabs are discussed, and then we discuss how to further refine the search results by imposing filters. Contents of page/chapter: +Common Options +Observation (AOR) Tab +Level 1 (BCD) Tab +Level 2 (PBCD) Tab +Filtering -- Imposing additional filters to get the most out of your search results +Restricting data in other tabs +Tagging -- Tagging a search so that you can reference it later. +IRS Enhanced Products Tab +Super Mosaics Tab +Source List Tab +Contributed Enhanced Products Tab +Orbit Precovery Search Results For an introduction to terminology, please see this summary in the overview section. Common Options Downloading Data In order to download data, click on the checkbox to the left of the entry you want to download, and then click on the "Prepare Download" button at the top of the column. (Select all of them at once by clicking the checkbox at the top of that column.) The Background Monitor is then launched to prepare your data for download. When your packaged data are ready, save your data to disk. (The Contributed Enhanced Products are a little different; see below.) Note that you control where the data are saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. For some overly helpful browsers and small downloads, it may appear to have not done anything; it just did it transparently quickly. Red lines -- some searches may return lines that are shaded red. These data cannot be downloaded because they are still proprietary. If they are your data, log in and you should be able to download them. If they are not your data, you can download those data after they become public, usually about 12 months after they were taken. You can add the release date as one of the additional columns to display in the search results pane. Restricting data in other tabs By default, the search results come up with a list of all returned AORs in the AOR tab and a list of a lot Spitzer Heritage Archive: Search Results 28

30 of corresponding files in the Level 1 and Level 2 tabs -- and it can be a long list -- for ALL of those AORs. These specific files vary according to the observation; they include the pipeline products such as a mosaic or extracted spectrum that is probably the primary goal of your search. If you want to limit exactly which files are listed in the Level 1 and Level 2 tabs, be sure that the "Restrict data in other tabs" box is checked (it should be by default) and then check the box in the row you want to examine. This is most conceptually straightforward if you select an AOR entry and then examine all of the Level 1 and/or 2 files that correspond specifically to that AOR, as opposed to selecting one of the subsidiary files and then going to another tab, though it works that way too. Note that the enhanced products tabs are different. The SHA can't take you back to the AORs from the contributed products (since some were created from intermediate processing versions); the SSC-generated enhanced products include within them pointers to the original AORs that were used to create them, but this is not currently retrievable via a single click within the SHA. Saving the results The search results can be saved to a text file by clicking the "Save" button or viewed as a text file by clicking the "Text View" button. Various information is included in the header of the file to give some indication of the origin of the search. Filtering Filters can be added interactively -- see Filtering below for more information. Adding/removing columns or rows Several columns come up in each of these tabs by default, and the default number of rows returned is 50 per page. These values can be changed by clicking on the table options on the far upper right of the corresponding tab's columns ( ). If you can't see this icon, it may be that the results pane is too small; grab the divider between panes and slide it to the right until you can see this icon. Note that the entire set of results can be sorted alphabetically by clicking on any column's name. Note also that if you resize columns, and then go and add new columns, the original columns are resized back to their defaults after the new columns are added. You can scroll through pages by the arrows on the top center of the search results and see how many rows there are total via the count indicated there. Do you have "too many rows" to easily sift through? Further restrict the search by imposing additional filtering; see below! Note that expanding the page size to numbers much greater than 50 may result in a substantial performance degradation (e.g., your browser will appear to freeze or not appear to be doing anything while it manages and renders the large table). Getting more information on any row Letting your mouse hover over many items will reveal some information in a "tool tip". Selecting any of the table entries results in different items appearing in the Details Pane. Please see that section for more information. Changing the size of the window or columns You can click and drag the divider between the columns or window pane. There is also a pair of black arrows ( ) that appears in the upper right corner of any window pane when your mouse hesitates; clicking on that expands the window to take up the whole browser window. To return to the prior view, click "Close" in the upper left corner of the expanded view. Spitzer Heritage Archive: Search Results 29

31 Observation (AOR) Tab (An individual Spitzer observation is an AOR, or Astronomical Observation Request; see terminology above.) Each AOR that was found via your search is returned here in this tab. Because each AOR can result in many other files, this AOR tab is the best place to start browsing! (The other tabs -- Level 1 and Level 2 -- will have more additional files listed per AOR, and once you download the data, you'll have even more files that come with the download. The enhanced products will have a different sort of diversity of files, depending on which products are available.) Column Headings: The target name was supplied by the original observer and may be enlightening or cryptic. The RA and Dec are the target of the AOR as observed. If the object was observed as a moving target, the NAIF ID is listed; otherwise, this is blank. The instrument and observing mode are listed next. The AORKEY is a large integer that uniquely identifies this observation in the SHA. The AOR label was supplied by the original observer and may be clear or it may be cryptic. The Observation start time is the time, in UT, that the observation was begun. The Program ID is the integer identifier for the program under which these observations were obtained. The Principal Investigator (PI) for these data is listed last in the default display. An additional column can be added which indicates whether the observation was an AOR or an IER; other columns can be added as well. (click on at the top right of the tab window to do this.) Do you have "too much data" in the subsidiary search result tabs? See restricting data in other tabs -- for example, limit the Level 1 and Level 2 tabs to be just the files from one AOR. Do you have "too many rows"? Further restrict the search by imposing additional filtering -- for example, limiting it to be just IRAC channel 1 data. In summary, restricting data in other tabs means selecting the checkbox for a row of the table and seeing the files corresponding to that row in the other tabs, whereas filtering corresponds to limiting the rows to specific values in the columns. (More information on using the details pane.) (More information on options found in every tab.) Level 1 (BCD) Tab (The individual data frames that emerge [calibrated] from the Spitzer pipeline are Level 1, or Basic Calibrated Data, or BCDs; see terminology above.) Each AOR that was returned by your search can result in many other files. This Level 1 (BCD) tab contains all of the BCDs that correspond to the AORs returned (or selected) in the AOR tab. (Additional Level 1 products will arrive with your download, such as errors and masks.) Note: For IRAC subarray data, only Level 1 (BCD) data are returned. There is no Level 2 product. Column Headings: Spitzer Heritage Archive: Search Results 30

32 The AORKEY is a large integer that uniquely identifies this observation in the SHA. (Note that each AOR results in many files, and that you can restrict the contents of this tab to be just those files corresponding to one AOR; see "Restricting data in other tabs" above.) The BCD ID is a large integer that uniquely identifies this particular file in the SHA. The instrument and observing mode are listed next. The specific bandpass of this individual file is in the next column. The RA and Dec are listed in hh:mm:ss dd:mm:ss format. If "no data" or other unusual values appear here, this is most likely a calibration file. The exposure time corresponding to this file is given in seconds. Particularly in the case of MIPS, the arrays may be on and collecting data even if the telescope is being used to observe using one of the other fields of view in the instrument. For any given row, if the telescope was optimized for use of the field of view to which the specific file applies, then the "primary field" column is 1; other values indicate that this is serendipitous data. See the MIPS Instrument Handbook (available on the IRSA Spitzer website) for more information on how to use these data. Since there can be files at the BCD level that are not images (such as tables of data), the "File Type" column lists the nature of the file. "Image" will be the most common. The file name of the corresponding file once it is unpacked and resident on your disk is listed. The filename contains information about the instrument, channel, and originating AOR as well as the specific contents of the file; see the IRSA Spitzer website, specifically the Instrument Handbooks, for a comprehensive listing of the files available at the BCD level (Level 1). Several additional columns can be added to the BCD view. Most of these should be self-explanatory from the column headers (or the tool tips) appearing in the pop-up window that appears when you add columns (see more information on options found in every tab -- in brief, click on of the tab window). at the top right (More information on using the details pane.) (More information on options found in every tab.) Level 2 (PBCD) Tab (The products that come from combining these individual data frames [such as mosaics of individual pointings] are Level 2, or post-bcd, or PBCD data; see terminology above.) Each AOR that was returned by your search can result in many other files. This Level 2 (post-bcd) tab contains all of the Level 2 products that correspond to the AORs returned (or selected) in the AOR tab. (Additional Level 2 products will arrive with your download, such as errors and coverage maps.) Note: For IRAC subarray data, there are no Level 2 products. Column Headings: The AORKEY is a large integer that uniquely identifies this observation in the SHA. (Note that each AOR results in many files, and that you can restrict the contents of this tab to be just those files corresponding to one AOR; see "Restricting data in other tabs" above.) The instrument and observing mode are listed next. The specific bandpass of this individual file is in the next column. The RA and Dec are listed in hh:mm:ss dd:mm:ss format. If "no data" or other unusual values appear here, this is most likely a calibration file. Spitzer Heritage Archive: Search Results 31

33 Since there can be files at the BCD level that are not images (such as tables of data), the "File Type" column lists the nature of the file. "Image" will be the most common; IRS data results in a lot of tables. The file name of the corresponding file once it is unpacked and resident on your disk is listed. The filename contains information about the instrument, channel, and originating AOR as well as the specific contents of the file; see the IRSA Spitzer website, specifically the Instrument Handbooks, for a comprehensive listing of the files available at the PBCD level (Level 2). Several additional columns can be added to the PBCD view. Most of these should be self-explanatory from the column headers (or the tool tips) appearing in the pop-up window that appears when you add columns (see more information on options found in every tab -- in brief, click on of the tab window). at the top right (More information on using the details pane.) (More information on options found in every tab.) Filtering -- Imposing additional filters to get the most out of your search results Even if your search returned only one AOR, you could have many files that appear in the Level 2 (PBCD) or Level 1 (BCD) tabs. In order to quickly weed through what files appear in the tab and find/examine the file you care about, filtering is a very powerful tool. At the top of the tab window, there is this icon, which represents a filter: Click on it in order to add a filter. A text entry box appears above each of the current catalog columns, with a small version of the filter icon corresponding to that row on the far left. You can type operators and values in these boxes -- hit return after typing or click in another box to implement the filter. For fields with a limited set of choices, instead of a text entry box, a filter icon will appear; click on it to select from the available choices. For example, if you have searched on an IRAC AOR and would like to only view the files relevant to the 3.6 micron channel, locate the 'Bandpass' column, click on the filter icon, and select 'IRAC 3.6 um' from the pop-up with the list of choices. Hit return or click in another box to implement the filter. After you impose a filter, then the number of rows in the catalog is restricted according to the rules you have specified, and the "filters" icon on the top right of the catalog pane has changed to remind you that there has been a filter applied, in this case just one filter: also appears after you impose filters):.. To clear the filters, click on the cancel filters icon (which You can add additional filters to further restrict your list of files. Note that the filters are logically "AND"ed together -- that is, if you impose "Bandpass=IRAC 3.6 um" and "Bandpass=IRAC 4.5 um", no data will result, because no data are both 3.6 and 4.6 microns at the same time. If you want to see just the 3.6 and 4.5 micron data, select more than one bandpass from the pulldown by selecting "select multiple" and selecting the multiple options you want. A more complex but still common application of filters would be downloading all the most recent data from a given program (e.g., data from one program that have just been released). To do this: Search by campaign for the most recent campaign. Many AORs will be returned. Once the results appear, click on "Filters". Locate the "Program ID" column. If you have a text box, type "=" and the program ID you want. If you have a pop-up with finite choices, select the program ID you want. Just the AORs from that campaign and that program will Spitzer Heritage Archive: Search Results 32

34 remain. NOTE THAT the filters as imposed this way only apply to your current tab, even if "restrict data in other tabs" is selected! (See "Restricting data in other tabs" above for more information on this option -- in summary, restricting data in other tabs means selecting the checkbox for a row of the table and seeing the files corresponding to that row in the other tabs, whereas filtering corresponds to the values in the columns.) The available logical operators are : = which means 'equal to' (exactly!), e.g., the parameter on which you are querying (such as "Bandpass") is exactly equal to this value you are specifying (such as "IRAC 3.6um" from the pulldown). > which means 'greater than' < which mean 'less than'!= which means 'not equal to' (exactly!) >= which means 'greater than or equal to' <= which means 'less than or equal to' IN which means 'included within this list', e.g., the parameter on which you are querying (such as "Bandpass") is included within the list you are specifying (if the column filter is free-form text, type "value1,value2" and it will give you rows that have value1 or value2). LIKE which means 'resembles the text that is entered', e.g., the text resembles the text that you type in the box. Tag It -- Tagging a search Many of the papers published on Spitzer data include a list of all the individual AORKEYs (the integer number corresponding uniquely to each AOR) used for data discussed in that paper. This provides an easy way for readers to retrieve the data from the Spitzer archive, and links can be made from ADS directly back to the SHA. However, many papers use many AORs. Data tagging allows you to customize the data set you use so that the link back from ADS (or embedded in your paper itself) refers to a single unique identifier that corresponds to all your data. (That is, a single identifier, as opposed to a potentially long list of AORKEYs.) You yourself (independent of any publications) may also wish to repeat a search later on for any of a number of reasons. Tagging a search means that you can easily recreate it later. Once you have established a search that you like and wish to repeat in the future, click on the blue "History/Tags" tab near the top of the browser window, then click on the "Tags" tab. At this point, you can enter a name for your tag, then click on the "Tag It" button. It will then return the tag URL you can save and distribute. It also appears in your tagging history. If you have logged in, this tagging history is available to you any time you log into the SHA. To recreate the search, highlight the tag row you want, and click on the "Resubmit Search" button. To remove it, click on the "Remove" button. IRS Enhanced Products Tab (Enhanced Products come from combining AORs or doing post processing; see terminology above. The SSC has generated enhanced products for IRS.) Spitzer Heritage Archive: Search Results 33

35 The SSC has generated enhanced products for the IRS observations in the Archive. For complete documentation on these products (how they were generated, etc.), please see the IRS Instrument Handbook, available at the IRSA website. If there is an IRS enhanced product available that meets your search criteria, it is shown in the "IRS Enhanced" tab. Many columns are shown, including extraction information, observation information, synthetic photometry for a variety of bands, and links to a merged spectrum. You can access additional columns available for this product by searching the IRS Enhanced Products directly, e.g., not via a position search per se. Filtering and column operations (adding, removing, sorting) work in exactly the same way as they do through the rest of the SHA. Selecting any of the table entries results in different items appearing in the Details Pane, and the related tabs. Please see that section for more information. Super Mosaic (SEIP Super Mosaics) Tab (Enhanced Products come from combining AORs or doing post processing; see terminology above. The SSC has generated enhanced imaging products (SEIP) for IRAC and MIPS-24.) The SSC has generated enhanced imaging products (SEIP) for the IRAC and MIPS-24 observations in the Archive. For complete documentation on these products (how they were generated, etc.), please see the Documentation for these products, available at the IRSA website. If there is a SEIP super mosaic available that meets your search criteria, it is shown in the "Super Mosaic" tab. The basic columns are shown, including RA, Dec, and the filename of the mosaic. Filtering and column operations (adding, removing, sorting) work in exactly the same way as they do through the rest of the SHA. Selecting any of the table entries results in different items appearing in the Details Pane, and the related tabs. Please see that section for more information. Source List (SEIP Source List) Tab (Enhanced Products come from combining AORs or doing post processing; see terminology above. The SSC has generated enhanced imaging products (SEIP) for IRAC and MIPS-24.) The SSC has generated enhanced imaging products (SEIP) for the IRAC and MIPS-24 observations in the Archive. If there is a SEIP source list product available that meets your search criteria, it is shown in the "Source List" tab. The columns that are shown by default include RA, Dec, quality flags, and flux density measurements at a variety of bands, including 2MASS and WISE. For complete documentation on these products (how they were generated, what these quality flags mean, etc.), please see the Documentation for these products, available at the IRSA website. Additional columns listed in the documentation but not shown in the SHA interface can be accessed via Gator. Filtering and column operations (adding, removing, sorting) work in exactly the same way as they do through the rest of the SHA. Spitzer Heritage Archive: Search Results 34

36 Selecting any of the table entries results in different items appearing in the Details Pane, and the related tabs. Please see that section for more information. Contributed Enhanced Products Tab (Enhanced Products come from combining AORs or doing post processing; see terminology above. The community has contributed many enhanced products to the archive.) Most of the enhanced products currently available via the SHA come from the deliveries made back to IRSA from the Legacy Teams, though other teams including the Exploration Science teams have also made deliveries. (More on enhanced product searching.) In response to a search, the Contributed Products Results tab comes up with a "Summary View" of the search results. By default, the results are grouped by type -- images, catalogs, or spectra. You can also choose to sort the results by originating project. The images come up quickly, and the summary page indicates how many images from each project are returned. Note that sometimes this could mean one image for each band, or it could mean image, errors, and coverage for each band, or it could mean multiple resamplings of the same bands, etc. To investigate exactly what images are available, click on the first link in each line, the one corresponding to the delivering project's name. Additional tabs are spawned for each click, containing a summary of the contents of each image or catalog. You can make those tabs go away when you are done with them by clicking on the x that appears when you put your mouse on the tab. Please consult the original documentation that came with the delivery for definitions, explanations, and caveats that might go with each product. Note that some teams delivered, e.g., GALEX and Halpha images, so you may obtain non-spitzer data from the Spitzer Heritage Archive! The delivery documentation can be found on the project's page in IRSA, which can be obtained by clicking the second link in each line in the summary, the one that tells you more about the delivery. Catalogs come up more slowly (because they are harder to search!), and depending on your search, the SHA may tell you that it has completed searching on "8 of 10 catalogs" or a similar phrase. Here too, the catalog contents vary across projects, and even between deliveries within the same project. In the case of the catalogs, the "count" tells you how many individual catalog entries there are in that catalog for your search parameters. Click on the first link in each line, the one corresponding to the delivering project's name, to spawn an additional tab with the catalog values. Note that by default, only 50 lines are shown, but as these catalogs can be very long, it may take a second or two to read in and render. The catalog columns as displayed are exactly as provided by the original Legacy team (with some additional columns added by IRSA to reformat the RA/Dec into standard options), so the columns are effectively different for each catalog. Please consult the original documentation that came with the delivery for column definitions, caveats, etc. Such information can be found on the project's page in IRSA, which can be obtained by clicking the second link in each line in the summary, the one that tells you more about the delivery. NOTE: Currently, the Contributed Products search performs a cone search of the IRSA holdings, and if you go to IRSA directly to do what seems to be the identical search on the same source material, it does a box search. This will result in some apparent inconsistencies (e.g., different numbers of images or sources) as a result of the corners of the box search area. For a complete background on the Legacy program, information on individual programs, and information on Spitzer Heritage Archive: Search Results 35

37 individual deliveries, please click the link that appears next to each project's entry on the summary. This will take you to the IRSA page corresponding to the project, from which you can learn more about the project and its deliveries. Visualization here is similar to visualization elsewhere in the SHA. You can investigate the observation coverage and overlay catalogs on an image. Orbit Precovery Search Results The search results for a Solar System Object Orbit precovery search are presented in a very different way than those for the other searches discussed here. Because it is looking for a series of observations of something that is moving on the sky, it presents the results of that search as a series of tiled images, as opposed to a list of observations. You can switch between these views via this pair of "view options" in the upper right of the results page: view. The left icon is the tiled view, and the right icon is the table or list Image Previews: In the tiled view, similar to the moving object search in the WISE Image Service, each image in which the position of the input object is predicted to have been covered at the time of observation. The predicted position is indicated by a blue square on the image. An orange "x" indicates the predicted position of the input object in previous or subsequent images (or image sets). Clicking on any of the positions will highlight (in blue) all the corresponding positions in the surrounding images. Orbital Path Coverage : The Orbital Path Coverage tab in the coverage pane displays the orbital path (blue line) of the input object during the time limits specified. The observations returned by the search of the orbital path are indicated by orange "x" symbols. Table (or List) View: The table of results provides a list of all individual images in which the predicted position of the input moving object is predicted to appear, given the input orbital path. Spitzer Heritage Archive: Search Results 36

38 The Details Pane: Getting More Information on a Search Results Row After you have searched the archive and explored the tabs in your search results, you might be interested in understanding the additional information that appears on the right side of your screen when a row in the table (for any tab) is highlighted. You can click and drag the divider between the window panes to resize them, or in several cases, you can click on the expand icon ( ) to expand that pane to take up the whole browser window. To collapse it back, click on "Close" in the upper left. The contents of the Details pane change according to which tab you have in the foreground, and which row you have selected. Depending on which tab you have in the foreground in the Details pane when you click on a different tab in the Results pane, or which tab you have already examined, you may end up with an "extra" tab in the Details pane, e.g., one more than is described here. This is the SHA trying to be helpful, preserving a vestige of what you were doing prior to changing tabs. Contents of page/chapter: +Details Tab +Data Tab +AOR Depth of Coverage Tab +AOR Footprint Tab +Data Coverage Tab Details Tab From any results tab, click on any row (note: no need to select the checkbox on the far left of the row). The row becomes highlighted in green. The details pane on the right side of the window changes accordingly. If it's not selected already, select the "Details" tab. The Details tab contains information about whatever line you have selected in the results pane. For AORs, it starts with a section that contains the original program title, program name, primary science category, principal investigator, and abstract. You can use this information to understand what the original observer was trying to achieve with these observations -- e.g. if they were attempting to observe bright things, it may be unlikely that you will be able to use those observations alone to study faint things. The rest of the Details tab contains additional technical information about the observation, such as the AORKEY (a large integer that uniquely identifies this observation in the SHA) and the observing mode parameters that defined this observation (such as frame time and dither pattern). More information about these parameters and their available values for any given instrument or mode can be found at the Spitzer Heritage Documentation website at IRSA. For Level 1 or Level 2 data, the Details tab contains technical information about the specific data frame or data product you have selected in the results pane. You can use this information to help decide if you are interested in finding out more about this frame or product, or deciding to download it. Most of the values that appear there should be self-explanatory from the name or from the tool tips that appear when you let your mouse hover over Spitzer Heritage Archive: Details Pane 37

39 the name. Much of the information that appears there is also information that can be found in the FITS header of the corresponding FITS file; for a full view of the FITS header, see the Data tab, specifically some of the visualization options that appear in that tab. For IRS Enhanced Products, the Details tab contains technical information about the specific data product selected. For Contributed Enhanced Products, you need to click on one of the projects first, and then you are taken to a list of all the returned products from that project. From there, you can select a row, and get a Details tab with information about that product. Data Tab From ANY results tab, click on any row (note: no need to select the checkbox on the far left of the row). The row becomes highlighted in green. The details pane on the right side of the window changes accordingly. Select the "Data" tab. NOTE: this tab shows you actual data. For AORs, the Data tab will either not appear, or retain its values from whatever you were last looking at. For Level 1 or Level 2 images, the Data tab shows you the actual data frame corresponding to the file you have selected. You can interact with the FITS image using the toolbox, which appears near the top of your window when you place your mouse over an image and hesitate. Further discussion of these can be found in the Visualization section. For Level 1, Level 2, or IRS enhanced spectra, the Data tab shows you the actual spectrum pulled from the file you have selected. In the case of IRS Level 1 or Level 2 data, both images and spectra are viable products; the "File Type" column in the AOR pane tells you whether the file is an image or a table, and thus whether to expect an image or a spectrum to appear when selecting the Data tab. All of the IRS enhanced products are spectra, and so the spectrum viewer will always appear. Discussion of all of the options for the spectrum viewer can be found in the Visualization section. For Contributed Enhanced Products, you need to click on one of the projects first, and then you are taken to a list of all the returned products from that project. From there, you can select a row, and get a Details pane that includes a Data tab, from which you can investigate that product. You can click and drag the divider between the window panes to resize them, or you can click on the expand icon ( ) to expand that pane to take up the whole browser window. To collapse it back, click on "Close" in the upper left. (More information on visualization options.) AOR DoC Tab From the AOR tab, click on any row (note: no need to select the checkbox on the far left of the row). The row becomes highlighted in green. The details pane on the right side of the window changes accordingly. Select the Spitzer Heritage Archive: Details Pane 38

40 "AOR DoC" tab. The AOR DoC tab shows you the depth of coverage (DoC) of the selected observations, e.g., how many individual frames were observed on each patch of sky. For any given AOR, the exposure time of an individual frame is [largely] the same for a given channel; the DoC tells you the number of frames, so the DoC is directly related to the total integration time per patch of sky. To find what that exposure time was, examine the information in the Details tab. IMPORTANT NOTE: The DoC is counting frames that were actually observed. This may sound simple, but it can be complicated. If your observation has frames of a variety of exposure times (e.g., certain long IRAC integrations sometimes have a short initial exposure for reasons related to instrumental effects), you will see an "additional" frame in the DoC. Since the DoC calculation works from the actual pipeline-processed data, it may have "additional" frames compared to a Spot visualization, since Spot was estimating what would be observed, as opposed to working from what was actually observed. If you have questions, please consult the corresponding Instrument Handbook, or contact us. The top of the AOR DoC window shows the zoom factor, and the wavelength to which it refers. You can scroll between bandpasses if more than one were obtained in the observation you are inspecting. You can interact with this DoC (which is a FITS file) via the image toolbox, which appears near the top of the window when you place your mouse over the image and hesitate. Further discussion of these can be found in the visualization section. This tab is "sticky", meaning that once you look at it once, it sticks around. You have to be somewhat careful - it will automatically update if you, say, pick another row in the AOR tab, but if you are in one of the other tabs, this tab will not go away, and not update. Note that it doesn't have any physical meaning in the enhanced product tabs. (More information on visualization options.) AOR Footprint Tab From the AOR tab, click on any row (note: no need to select the checkbox on the far left of the row). The row becomes highlighted in green. The details pane on the right side of the window changes accordingly. Select the "AOR Footprint" tab. The AOR Footprint tab is meant to show you the specific region of sky that was covered by the selected single AOR. Note that this is the entire observation, all bandpasses. The background image that comes up by default is automatically selected (you can change it), and the outline of the observation (its "footprint") is drawn on the image. You can interact with the AOR footprint image (which is a FITS file with an overlaid footprint) via the image toolbox, which appears near the top of the window when you place your mouse over the image and hesitate. Further discussion of these can be found in the visualization section. The top of the AOR Footprint window shows the AORKEY corresponding to the visualized AOR, the source of the background image used, and the zoom factor. (More information on visualization options.) Spitzer Heritage Archive: Details Pane 39

41 Data Coverage Tab From just about any tab other than the AOR tab, click on any row (note: no need to select the checkbox on the far left of the row). The row becomes highlighted in green. The details pane on the right side of the window changes accordingly. Select the "Data Coverage" tab. NOTE: this tab shows you portions of the sky covered by the ALL the files that are displayed in a given page. This is one of the most common confusions about this tab. Note that it is not all the search results (if you have more than one page), and it is not just the single row you have selected. The Data Coverage tab shows you the portion of sky that is actually covered by the screenful of files you have displayed. This is different from the AOR Footprint tab in that the AOR Footprint tab shows you the portion of sky observed by just the entire single AOR that you have highlighted. The background image that comes up by default is automatically selected (you can change it), and the outlines of all the observations in the window are drawn on the image. The specific one corresponding to the row you have selected is highlighted in a different color. (You have some control over which colors are available for these overlays - see the Visualization section.) You can use this feature, for example, to determine the portion of a large map that you wish to download and further analyze, or the specific frame that hits a bright star, etc. Note that the Data Coverage will just show the pointings corresponding to the files listed in your current window! If you have 72 files returned but are only looking at 50 at a time, then only the first 50 will be visualized. To see the full AOR coverage, use the AOR Footprint tab, or increase your page size (see text here), and/or impose filters. For Contributed Enhanced Products, you need to click on one of the projects first, and then you are taken to a list of all the returned products from that project. From there, you can select a row, and get a Details pane that includes a Data Coverage tab, from which you can investigate the sky coverage of that product. You can click and drag the divider between the window panes to resize them, or you can click on the expand icon ( ) to expand that pane to take up the whole browser window. To collapse it back, click on "Close" in the upper left. Again, the images that are shown are real FITS files, and you can interact with them using the image toolbox. Further discussion of these can be found in the visualization section. Spitzer Heritage Archive: Details Pane 40

42 Visualizing data in the Spitzer Heritage Archive Contents of page/chapter: +Overview +Basic FITS Image Viewer +Visualization Tools -- Image Options +Footprints -- overlaying markers +Spectrum Viewer +Breaking out of the pane (and going back) +World Coordinate System (WCS) Alignment Overview Powerful visualization tools were important to the original Spitzer observation planning and archive tools (Spot and Leopard), and the descendents of these tools are included in the SHA. These tools can be used to understand exactly what each observation did and in deciding what data to download. FITS images from Spitzer or other bands (or from your computer) can be loaded into the viewer. If performing an SHA search, the footprint of the observation can be overlaid on an image of your choice. Individual data products can be viewed interactively and flux density levels assessed. The viewer within the SHA itself can be found in two places. Clicking on "Read FITS File" on the top set of blue tabs allows you to load a FITS file from disk or from a variety of online sources, resulting in a visualization-only panel. Alternatively, and perhaps more frequently encountered, once a search is completed, several of the tabs in the Details pane on the right result in a window with an image (or a spectrum) so that you can examine the data interactively. Please see details pane section for complete information, but in summary, there is one tab entitled "Details" that has text, and the rest have various representations of the data. Basic FITS Image Viewer All of the interactive image visualization tools work the same basic way, and here we describe these basic options, in roughly the order in which you might encounter them in the window. Interactive exploration of the image with the mouse. Move your mouse over any image that is loaded into the SHA. Details about the image and, specifically, the pixel beneath your mouse cursor, appear along the top of the window with a variety of useful items. Some information is updated in real time (such as coordinates); some information (such as flux densities) is updated when you stop moving your mouse for a second or two. The image can be interactively investigated in this fashion. You can make it 'stick' on a particular place on the image -- tick the "Lock by click" box and then click on the image at your desired location. Spitzer Heritage Archive: Visualization 41

43 The orientation of the image is given with a compass rose on the right, next to a zoomed-in view of the image under your cursor. If you can't see all of these two windows, enlarge your browser window slightly. Finding out more about the displayed image. The top of the display (just under the tab headings) gives a title of the image. This abbreviation may be a little cryptic. ISSA or IRIS are both IRAS data. 2MASS comes up by default to be used for small fields of view, and as such, the Spitzer fields of view may be off the edge; this will be fixed in a later release. Some of this information (like the title of the image) is also given in the interactive exploration region described immediately above. This region also includes additional information about the image (such as the pixel scale and orientation). Visualization Tools -- Image Options There is a toolbox along the top of the IRSA Viewer window: from which you can select a variety of options, now described. Letting your mouse hover over any of these icons will result in a "tool tip" that appears in order to remind you what the icon does. This information is also dynamically updated just to the right of the toolbox itself. Saving the image. The diskette icon will allow you to save the current image as a FITS or PNG or Regions file to your local disk. Note that you control where the file is saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. Saved FITS images will not save the color stretches or overlays; it will just save the underlying FITS image. Saved PNG files WILL include any overlays or annotations you have placed on the image, but will not include the underlying FITS image. Saved regions files will not save the underlying image, but will just save the overlays as a DS9 Regions file. See the DS9 website for more information on the syntax of these DS9 region files. Note that you can save the original or a cropped version of the FITS file; see the select region icon below to crop, and then save the FITS image. Note also that if you overlay a catalog consisting of tens of thousands of sources, to save bandwidth, what is overlaid on your image at some locations may be a larger symbol representative of several sources at that location; if you save a regions file from the catalog overlay, then you will have fewer sources in the regions file than you have in the full catalog. Selecting a new image Depending on what you're looking at, you may or may not have this icon. If you are looking at a non-spitzer image on top of which is placed footprints if Spitzer observations, you have a choice of the background image. By default, the SHA tries to pick a good background image, but you may wish to try another wavelength or field of view. By clicking on this icon, you bring up a pop-up window. The first part of this window shows the central RA/Dec that you are about to request (you can change this by clicking on "Modify Target" and all the usual options appear). The next part of this window has a series of tabs: IRAS (12, 25, 60, and 100 microns), 2MASS (J, H, and Ks bands, or 1.25, 1.65, and 2.17 microns), WISE (3.4, 4.6, 12, and 22 microns), MSX (8.28, 12.13, 14.65, and 21.3 microns), DSS (the Spitzer Heritage Archive: Visualization 42

44 usual red/blue plates and a variety of scan options), a FITS file from your local disk, or a URL that you can enter so the browser can retrieve a FITS file from the web. From this pop-up, you can also choose to create a 3-color image, loading a new FITS file separately for each color plane. Note that this 3-color option only appears for background images, not Spitzer data, unless you already have Spitzer data on your disk that you can load into the visualization tool. Lock the image Depending on what you're looking at, you may or may not have this icon. If you are looking at a non-spitzer image on top of which is placed footprints if Spitzer observations, you may wish to lock the underlying image so that you can add additional annotations or overlays to the image. Clicking on this icon brings up a pop-up from which you can choose to lock the image (or load a new one). Zooming in or out. Clicking on these magnifying glass icons zooms in or out of the image. The readout of how many times you are zoomed appears at the top of the visualization window. If you click zoom in or out rapidly, a pop-up window appears to allow you to more rapidly select the zoom level you want. Select the desired level, or click on the blue 'x' in the upper right to make the window go away. Here is an example: Note that there is a maximum (or minimum) allowed zoom level. A notification will appear when you have reached the maximum (or minimum) allowed zoom level for a given image. To enlarge things more than that, please repeat your search to obtain new images with smaller (or larger) spatial extent. Zooming to a 1-to-1 size. Clicking this icon will zoom the image such that one pixel in the image is one pixel on your screen.. Fit image to screen or fill screen These two icons are designed to maximize the available space in your browser window. The first one automatically picks a zoom level such that the image entirely fits within the available space. The second Spitzer Heritage Archive: Visualization 43

45 one automatically picks a zoom level such that the image fills as much of the available space as possible (e.g., it is zoomed such that short axis of the window is filled with the image, whether that short axis is left-right or up-down). By default, the images that are returned are frequently but not always centered on your search target. Clicking on these icons let you see the whole image that is returned, whether or not it is centered on your target. Changing the color table. This icon enables you to change the color table of the displayed image. When you click the button, a pull-down menu appears with a wide variety of color table choices. Select your new color table from the options shown: Changing the color table stretch. This icon enables you to change the color table stretch of the displayed image. When you click the button, a pull-down menu appears with a variety of choices. You can choose from a set of pre-selected options: Spitzer Heritage Archive: Visualization 44

46 If you pick the first one, "color stretch", you can customize the stretch. A pop-up window appears with a histogram of the values in the image, and you can change the stretch type and range. If you pick a color stretch from the pre-defined options, the pop-up window reflects this change. (Ex: pick 'Linear stretch to 99%'. Go back to "color stretch". Note that it has filled out the stretch type and ranges to reflect the current choice. Then -- either with the pop-up window still up or not -- go back and pick a different pre-defined stretch from the standard options. Note that the values in the pop-up change to reflect this current choice.) Rotating the image to any angle This feature allows you to rotate the image to any angle of your choice, in degrees. It will rotate the image counter-clockwise (to the left) from the current view, not necessarily the original image. For example, entering "45" in the rotation pop-up and hitting "rotate" will rotate the image 45 degrees counter-clockwise relative to its original orientation. Then selecting the icon again, and entering "180" in the pop-up (followed by hitting "rotate") will rotate the image an additional 180 degrees counter-clockwise. To exit the pop-up without making further changes, hit the blue 'x' in the upper right of the pop-up. Spitzer Heritage Archive: Visualization 45

47 Rotating the image so that North is up. Images used as background images (for. e.g., the AOR Footprint) are commonly already oriented such that North is up, or close to it. However, actual data frames from the pipelines or contributed products may not have North up. Clicking this icon will orient the image so that North is up. Flipping the image on the y-axis. Clicking on this icon flips the image on the y-axis. Re-center the image. Clicking this icon will re-center the image on the center of the last query, or on the center of the image. Selecting a region. When you click this icon, at first, nothing seems to happen. (There is a notice with brief instructions that appears on the lower left of your browser window.) You can now click and drag in the image, selecting a box on the image. This box can be resized by grabbing and dragging the corners of the box. You can make a new box right away by holding down the shift key and clicking and dragging to select a new box. When you have selected a region of the image, additional icons appear above the image: These icons will allow you to (from left to right) crop the image to the selected region, obtain statistics on the region, select the catalog sources overlaid on the image within the region, or filter the overlaid catalog down to the enclosed sources. (The last two options will only appear if you have a catalog overlaid.) You can save the cropped FITS image via the save icon (described above). The statistics option results in a pop-up that looks something like this: Selecting sources highlights them in the catalog list. When you impose a filter, the filters icon changes above the catalog to indicate that there is a filter applied (in this case just one filter: filters, click on the cancel filters icon (which also appears after you impose filters):. ). To clear the Measuring a distance. When you click this icon, at first, nothing seems to happen. However, you can now click and drag to draw a line on the image, and the length of the line is displayed (in the middle of the line). The units for the measured distance (and the color of the overlay) can be changed from the "layers" icon (described below). You can calculate the difference in RA and Dec separately via the layers icon as well; find the layer associated with the distance measurement and tick the "offset calculation" box. When it displays the offset calculation, it will give you the angle in degrees in one corner, and the length of the line segment in the RA and Dec directions, in the units you have specified. Put a marker on the image. Spitzer Heritage Archive: Visualization 46

48 When you click this icon, a pull-down menu appears with several possible options: The first overlay choice (simply called 'marker') is a red circle. Initially, it appears in the center of the images, and is meant to be moved to wherever you first click in the image. It looks like this:. The small circles in the four corners are "handles" -- you can grab the handles to resize the circle. You can also drag it to any location in the image. You can change the color of the marker (and add a label to it) via the "layers" icon (described below). You can also remove this layer via the layers icon. There are several additional options in the pulldown, enough that they have their own section below. Show the directions of North and East When you click this icon, arrows appear on the image showing which direction is North and which is East. Add a coordinate grid. Click on this icon to overlay a coordinate grid on the image. Click it again to remove it. Customize the units of the grid (to, e.g., Galactic coordinates) via the "layers" icon (described below). Read in a DS9 Regions file When you click this icon, you get a pop-up window from which you can read in a DS9 regions file from your local disk. See the DS9 website for more information on the syntax of these DS9 region files. The supported regions are text, circle, box, polygon, line, and annulus. To make this window go away without doing anything, click on the blue 'x' in the upper right of the pop-up. Viewing/changing the layers on the image. If you've been following along by trying these various options, you now have an image with a lot of annotations on it. The number that appears in blue over the layers icon tells you at any given time how many layers you have on the currently selected image. If you click this icon, you will get a pop-up window with a list of all the layers you have on top of the image. From the pop-up, you can turn layers off and on, at minimum, but you can often also change exactly what is displayed and what colors get used for it. To add new things, though, you need to go to other options within the toolbar. Here is an example of a well-populated layers pop-up. Spitzer Heritage Archive: Visualization 47

49 To change colors of a layer, click on the 'colors' link to be taken to a new pop-up from which you can select a new color. To delete a layer, click on 'delete'. Some layers appear do not have that option; to remove that layer, click on the corresponding icon from which you added that feature. To make this pop-up window go away, click on the blue 'x' in the upper right of the pop-up. Restoring everything to the defaults If you've played around a lot with the image, you may want to undo everything you've done. Click this button to restore everything to their original default values. Some layers may persist; remove them via the layers icon described above. Viewing the FITS header. This icon will display a pop-up window with the FITS header of the background image. If you click on the columns of the FITS header in the pop-up, it will sort the keywords alphabetically by that column. This is useful for finding individual keywords in particularly densely populated FITS headers. Click the header again to sort in reverse-alphabetical order, and a third time to return to the default order. Here is an example of a sorted FITS header. Note that the first column is the original order of the keywords. To make it go away, click on the blue 'x' in the upper right of the pop-up. Spitzer Heritage Archive: Visualization 48

50 Getting help. Clicking on this icon takes you to this help page. Also see the information on retrieving and using catalogs, because you can overlay catalogs on your images. Footprints The marker icon ( ) has a pull-down menu with several possible options: We now describe these options here. For each of these choices, the markers appear initially in the center of the loaded images. The first mouse click you make in any of the images will move the marker to that location. Spitzer Heritage Archive: Visualization 49

51 Each of these marker choices, when overlaid and/or selected as 'active', has a large circle surrounded by 4 small circles located at the edge of the large circle. These so-called "handles" allow you to resize and/or rotate the marker, depending on the nature of the marker. These handles only appear when the marker is selected as active, and they are in the same color as the marker itself. From this marker icon pull-down, by default, it comes up with each option as "show". When you select that option, the marker appears in the layers pop-up (described above), from which you can hide/show the marker, or change its color. Note that after you add a marker, the pulldown menu here changes for that marker menu option to be "hide all" in front of that marker menu option. You can add multiple copies of the same marker using the layers pop-up (described generally above). You can also add a label to the marker from the layers pop-up. The first overlay choice (simply called 'marker') is a red circle. The remaining markers are all footprints from other space-based telescopes: HST, JWST, and WFIRST. These footprints are derived from information provided via MAST (see For JWST and WFIRST in particular, they are pre-launch values. HST focal plane footprint. Consult the HST documentation for specifics on which apertures are which. The footprint can be moved or rotated. Click and drag the center of the footprint. A circle appears with four small circles ("handles") around it. Grab and drag the small circles to rotate it, or drag the big circle to move it. Note that if you overlay the footprint on a very small image, nothing will appear to have happened. You need at least a 45 arcmin image to comfortably see the footprint. Change the color, delete, or add more copies of the HST footprint from the layers pop-up: JWST focal plane footprints. JWST Footprint Description Spitzer Heritage Archive: Visualization 50

52 JWST FGS Preliminary footprint JWST MIRI Preliminary footprint JWST NIRCAM Preliminary footprint JWST NIRSPEC Preliminary footprint JWST NIS Preliminary footprint JWST entire Preliminary footprint (cross is boresight) Note that if you overlay the footprint on a very small image, nothing will appear to have happened. You need at least a 30 arcmin image to comfortably see the footprints, especially the entire JWST focal plane. Please consult the JWST documentation for details about the footprints. In all cases, if the footprint is 'active', a circle near the middle of the footprint will appear with four small circles ("handles") around it. Grab and drag the small circles to rotate it, or drag the big circle to move it. Change the color, delete, or add more copies of the footprints from the layers pop-up, one example of which is given here: Spitzer Heritage Archive: Visualization 51

53 WFIRST focal plane footprint. As above, the footprint can be moved or rotated. Click and drag the boresight (the cross hairs), which appears by default to the upper right of the array of squares. A circle appears, centered on the boresight, with four small circles ("handles") around it. Grab and drag the small circles to rotate it, or drag the big circle to move it. Note that if you overlay the footprint on a very small image, nothing will appear to have happened. You need at least a 60 arcmin image to comfortably see the footprint, and even then you will probably have to click and drag to see the entire footprint. Consult the WFIRST documentation for specifics on the apertures. Change the color, delete, or add more copies of the WFIRST footprint from the layers pop-up: Spectrum Viewer Some of the data products associated with spectroscopy are images (e.g., the original images that were read out from the instrument), but reduced spectra can be viewed from any results tab (except for the AOR tab). These files appear as a "Table" in the "File Type" column of the results table. Select one of them in the results pane, and then look at the "Data" tab from the details pane, and you will be able to interactively explore the spectrum. Move your mouse along the spectrum, and a popup display shows you the corresponding wavelengths and flux densities. If you are getting no pop-up display, click once in the window to be sure your computer knows you are there. (This visualization tool can be used with any x-y plot, but in several SHA cases, it's used for viewing a spectrum.) Finding out more about the displayed spectrum. Spitzer Heritage Archive: Visualization 52

54 The top of the display (just under the tab headings) gives an indication of the observation and what is plotted. Expanding the spectrum. Clicking on this icon will enlarge the visualization window into a window that takes up the whole browser window. This also enables you to look at more than one visualization window at a time. More about the expanded view For the IRS enhanced products, some options are only available in the expanded view. In the expended view, you can turn on/off plotting of various orders and synthetic photometry points. There is more on the expanded view in general below. Zooming in or out. Unlike an image zoom, here you have something called "Rubber band zoom." Use your mouse to denote a region by clicking-and-dragging from the upper left to the lower right of the region on which you'd like to zoom. This region is then expanded in the viewer. To return to the original view, there is a link at the bottom of the viewer that says "Zoom out to original chart" which returns you to the default view. "Chart Options" For the spectrum visualizations, a "chart options" link is available in the lower left. This brings up a pop-up window entitled "XY Plot Options" with various configurable options to further manipulate your plot. In the pop-up, you have these options: Plot Error -- add the errors to the plot. They appear as a light grey 'envelope' around the spectrum. Plot Synthetic Photometry -- checked by default, this overplots the synthetic photometry that is part of the IRS enhanced product. If you are not viewing an IRS enhanced product spectrum, this option does not appear. Plot Style -- change how data are presented on the plot. The options are "Connected Points", "Unconnected Points", and "Line". Connected points shows the individual points and a line connecting them. Unconnected points shows just the individual points. Line shows just the line connecting the points. X min/x max and Y min/y Max -- manually change the range of the plot. You can also 'rubber band zoom', as per the above. Please note that unlike zoom, changing the range drops out-of-bound points, and some points that were not adjacent before might become connected as adjacent. X Column and Y Column -- change what is being plotted. Click on the blue circled "i" to get a list of the choices. Note that if you change what is plotted on the Y axis, the ability to overplot errors and synthetic photometry goes away. "Restore Default" undoes any changes you made, and "Apply" implements any changes you made. These options are preserved through the current search. It will be reset to the defaults in the next search, or when the search is redone. If the plot ever looks strange, go back and make sure that you have clicked 'Restore Default' in this pop-up. This always applies to the current plot. "Download Data Table" For all spectrum visualizations, a "download data table" link is available in the lower right. This will allow you to save the source data table which is being plotted. Saving a particular view Spitzer Heritage Archive: Visualization 53

55 The best way to save a particular view of a particular spectrum/zoom/annotation/etc. is to do a screen snapshot. The specifics for this vary according to your platform and OS version. On a Mac, this is accomplished via holding down command, then shift, then 4, then let go and your mouse cursor changes. Hit the space bar to select the window over which your mouse is hovering. Your mouse cursor changes again, and hit the mouse button. A snapshot is then saved to your Desktop, tagged with the date and time. Breaking out of the pane (and going back) By default, the search results are broken up into panes. For some purposes, it is useful to view either the table as large as possible, or the images as large as possible. If you let your mouse hover over just about any tab in any pane, this icon appears in the upper right of the pane. Clicking on it will expand the pane into a larger window, as big as possible given your browser size. If you expand an image, from this view, you now have some additional options that appear near the top of the new window. The large "Close" arrow at the left enables you to return back to the pane view. This arrow is always available in these expanded views. Next, the currently displayed band (sometimes using abbreviations) and magnification factor is shown. Zoom in or out using the visualization toolbox described above. Then, there is a cluster of icons that portray (in icon form) the different views you can have of the images you have loaded. (The current view has a light blue square around it.) The first icon (the big square) denotes "show one image at a time." The second icon (the cluster of four squares) denotes "show smaller images of all the images I have loaded, but still take up the whole browser window with the set" (as opposed to going back to the individual window panes). In the SHA, most of the time, you only have one image loaded. But, depending on what you have been doing in your session to this point, you may have more than one image loaded, plus a plot from the catalog. Perhaps you wish to see, e.g., just two of the images tiled? Click on the last, "list" icon in this cluster to bring up a pop-up window: This popup window lists all of the images you have loaded, and if you uncheck the corresponding box, that image, while it is still loaded, will not be shown if you, say, scroll through the images, or look at them in tiled mode. Spitzer Heritage Archive: Visualization 54

56 The next portion of the window has some WCS (world coordinate system)-related options that will be discussed below. Finally, on the right hand side, the arrows, labels, and green/blue dots (which only appear when you are viewing one image at a time) allow you to navigate through your set of images. The green dot inamongst the blue dots indicates where you are in the sequence of images, and the arrows and labels indicate which image is before or after the currently viewed image. Click on the arrows or the dots to move around in the sequence. World Coordinate System (WCS) Alignment In the expanded view ("broken out of the pane"), you have up to three checkboxes that may appear as viable options: "WCS Search Target Match", "WCS Match", and "Auto Play." ( ) However, depending on what you have loaded, these WCS options may not make sense or may not seem to have an effect (e.g., may not seem to affect the displayed images in any sensible way). They are: WCS Search Target Match This box is available whether you are looking in single frame or tiled frame view. Clicking on this box will align all of the displayed images to be centered on the target on which you searched (inertial or moving). Your search target is indicated by the blue circle. Clicking this option also aligns north up, and zooms such that the images fit in the available window, and aligns the images so that each image has the same angular scale. In essence, this is a one-click way of doing the following: locking all the images together, clicking on the "rotate North up" icon, clicking on the "zoom to fit" icon, and clicking on the "center on search target." This is particularly useful if you are looking for changes between multiple images of the same target, or following a moving target as it moves across multiple images. WCS Match This box is available whether you are looking in single frame or tiled frame view. The effects of clicking this box is similar to the prior "WCS Search Target Match" option, except that it aligns each image to the orientation, zoom, etc., of the image you have selected. (In tiled view, an image is selected by clicking on that image, and, once it is selected, the tile is outlined in orange. In single-frame view, the image you are looking at is the selected image.) Auto Play This box is only available in single frame view. This option blinks through all of the images you have loaded (and aligned). You may find that you have 'extra' images loaded, beyond what you wanted to blink. To remove those from the blink sequence, stop the blinking by unchecking the "Auto Play" box, click on the list icon immediately to the left of the checkboxes, which brings up a "Choose which" pop-up. Uncheck the images you don't want to show, click on "ok", and then go back and check the "Auto Play" box to blink the remaining images. (See above for more details on this process.) Once it loads and blinks through all the images at least once, it holds the images on the screen for 1 second before showing the next image. Note that the WCS options are "sticky", which means that if you click one, and then unclick it a few seconds later, it doesn't automatically "undo" the changes it made; to "undo" it, you either have to redo your search entirely, or click the "return to defaults" icon in the toolbox. To remove an image entirely, click on the small blue 'x' in the upper right of the image in the tiled view, or on the small blue 'x' in the corner of the image (or catalog) tab in the window pane view. Spitzer Heritage Archive: Visualization 55

57 Spitzer Heritage Archive: Catalogs You can choose from any of a wide variety of catalogs to load for overlaying on your visualized data. The catalog search option only appears once you have performed at least one search, e.g., you have something on which to overlay the catalog. Contents of page/chapter: +Overview +Catalogs from IRSA -- Overlaying catalogs from IRSA +Catalogs from disk -- Overlaying your own catalogs +Catalogs from VO -- Overlaying catalogs obtained via the VO +Columns and filters -- Interacting with catalogs +Plotting catalogs +Examples of catalog plots Catalogs -- Overview Once you have conducted a search and have some displayed images, you can perform a catalog search, which will (among other things) overplot those catalog sources on all the images shown. Catalogs are available via a blue tab that appears at the top of the page only after you have performed at least one search -- in essence, you need to have something on which to overlay the catalog before it will let you search. By default, it assumes you want to perform a catalog search that covers the same region as your recent search, and pre-fills the form with that region -- but you can choose to change those search criteria. You can choose from any of a number of catalogs. You can also upload your own catalogs. The catalog will be overlaid on the images in the details pane, such as data coverage and any data shown. The highlighted source will change depending on which source is selected in the catalog tab in the results pane. If you searched on the SEIP Source List from the main position search page, that catalog is overlaid on the images as part of the search results. You can turn a catalog overlay off temporarily via the "layers" icon. Catalogs from IRSA By clicking on the blue "Catalog" tab (which also looks like a button), a window appears with several options, as follows. By default, it pre-fills your search region to match what you have been doing with your current object. If you would like to change the region of the search for the catalog search, change the coordinates of the polygon it shows by default, or (easier), change the search method to "cone" and click on "modify target" and enter the new information. You can customize the search for options beyond a cone search (e.g., an elliptical search). The default cone radius is 500 arcsec. Caution: pick your units from the pulldown first, and then enter a number; if you enter a number and then select from the pulldown, it will convert your number from the old units to the new units. There are both upper and lower limits to your search radius; it will tell you if you request something too big or too small. Note that these limits are catalog-dependent. Spitzer Heritage Archive: Catalogs 56

58 You then need to specify the catalog you want to search. In order to help it give you a specific list of choices, you need to first tell it the project (default: WISE) and category (default: AllWISE Database). After you have selected these items, on the right, you can pick the specific catalog (default: AllWISE Source Catalog). To change catalogs, first select the "project" under which they are housed at IRSA, such as 2MASS, IRAS, WISE, MSX, etc. The options under the "category" and the specific clickable catalog on the right change according to the project you have selected. A short description is provided for each of the catalogs, with links for more information (including definitions of the sometimes cryptic column names); an example of this link for more information is here: You can also set restrictions on specific columns by clicking on "Set Column Restrictions" on the left hand side, under the "category" selection pull-down menu. A new window will open up with the available column names in the corresponding catalog, and you can choose what to display, and filter what is returned (for example, only return objects with values in column y that are greater than x). If you add more than one restriction, they are combined logically using an "AND" operators; be careful, because you can thus restrict data such that none of the catalog meets your criteria. Power user tip: By default, this interface may show you fewer columns than are available in the full catalog. By clicking on "Set Column Restrictions" and selecting "long form" from the pulldown at the top of the pop-up window ("Please select long or short form display"), you can access the full range of available columns. In some cases, there are literally hundreds of columns that you can access! Click on "Search" to initiate the search. It will load the catalog into a tab of its own as part of the search results pane. The objects will also be overlaid on any images you have loaded; you can also make an x-y plot from the results. (For more on the x-y plots, see below.) All of these representations are interlinked -- clicking on a row in the table shows it on the image and in the plot, and clicking on an object in the image shows it in the table and in the plot, and clicking on an object in the plot shows it in the table and on the image. (You can obtain a full-screen view of your catalog -- click on the expand icon in the upper right of the window pane when your mouse is in the window:. ) To close the catalog search window without searching on a catalog, click on "Close" in the upper left. Spitzer Heritage Archive: Catalogs 57

59 On the speed of the catalog results... If the catalog search is successful quickly, it will promptly return the results in a tab of its own. NOTE THAT the search may take a long time to return, especially if you have asked for a large catalog, and you may think that nothing has happened, but be patient and eventually it will either spin off to the background monitor (from which you can load it into a tab), or return a tab directly. Searches that take longer than a few seconds get spun off to the background monitor. If it does spin off to the background monitor, it will dynamically update to reflect its status, and will let you know when the catalog is ready to download or display. A popup appears asking if you want to load the catalog. Either click on the popup or explicitly open the background monitor and click on the catalog name to load it into a tab of its own. Use large search radii with caution! Be sure you understand how many sources you are likely to retrieve. Searches that retrieve more rows will take longer. Searches that retrieve millions of rows will take quite a while. Note that if you overlay a catalog consisting of tens of thousands of sources, to save bandwidth, what is overlaid on your image at some locations may be a larger symbol representative of several sources at that location; if you then save a regions file from the catalog overlay, then you will end up with fewer sources in the regions file than you have in the full catalog. Loading your own catalogs By clicking on the blue "Catalogs" tab, you are by default dropped into the interface for searching for catalogs at IRSA. However, you can pick another tab from the top left of the catalogs screen, "Load Catalog", to load your own catalog. Your catalog needs to be in IPAC table format, which is a varietal of plain text. IRSA has a table reformatting and validation service which may be helpful, or you can download just about any catalog you find through IRSA, and copy that format. Your table file MUST have RA and Dec values, and unless it is specified, it assumes J2000. You can add a "SYMBOL" parameter to change the shape (X, SQUARE, CROSS, EMP_CROSS, DIAMOND, DOT) of catalog marks, e.g.: \SYMBOL = X You can add a "DEFAULT_COLOR" parameter to assign a CSS color name or a HEX value to catalog marks, e.g., either of these two: \DEFAULT_COLOR = lightcyan \DEFAULT_COLOR = #00FF00 You can find the CSS color code or the CSS color HEX values online. Catalogs from the VO -- Overlaying catalogs obtained via the VO (VO= Virtual Observatory.) Spitzer Heritage Archive: Catalogs 58

60 By clicking on the blue "Catalogs" tab, you are by default dropped into the interface for searching for catalogs at IRSA. However, you can pick another tab from the top left, "VO Catalog", to search for and load catalogs from the VO. As for the IRSA catalog search, the tool pre-fills the target position with the coordinates of the target with which you have been working. In this case, you are limited to a cone search, so the next option is the cone search radius. As usual, pick your units from the pulldown first, and then enter a number; if you enter a number and then select from the pulldown, it will convert your number from the old units to the new units. There are both upper and lower limits to your search radius; it will tell you if you request something too big or too small. If you know your VO URL already, you can jump down to the Cone Search URL box and type or paste your URL into the box and hit search. More commonly, however, users do not know a priori which URL to use. Type your desired keywords into the keywords box and click on "Search Registry". All of the URLs it finds for your keywords within the VO registry service are shown in the box. Locate the one you want to use, and click on "Use" on the far left of the corresponding row. The "Cone Search URL" is populated properly for that catalog. Click on "Search" to initiate the search. The search results are then shown (and interacted with) in the same way as the other catalogs described here. Example Load the tool. Search on IC1396. Go to the catalogs tab. Choose "VO Catalog." It wants the root URL for a cone search. I click on "Find Astronomical Data Resources", which takes me here. Search on IPHAS. Get this page. Look for the complete catalog release (not just one associated with one specific study). The name of the catalog goes here. Hit the [+] to expand it. There is one URL listed there, under "available endpoints for the standard interface." Copy that URL and paste it into the search form. The IRSA tool will append your Spitzer Heritage Archive: Catalogs 59

61 coordinates and radius and return you a table. Troubleshooting Note that searching the VO means that you are using resources not specifically housed at IRSA, so servers may be down, or timeouts set, or limits on numbers of returned sources, etc., that are beyond our control. In most cases the solution is to specify as precise a search as possible. Here are the links to VO registries that we are using, just in case you want to do more flexible searches of the registry. The URL you enter into the box in Finder Chart, though, must be a Cone Search base URL (not containing RA and Dec parameters, which are inserted into the URL by Finder Chart in response to the search parameters you give it). The master list of registries is here. You can also search the registries directly via that link (as opposed to via the IRSA tools). Columns and filters with catalogs After you have loaded a catalog, it appears as an additional tab in the search results pane (on the left); all the catalogs you choose to load are in their own tab within the search results pane, one tab per catalog. The objects will also be overlaid on any images you have loaded, you can also make a x-y plot (for more on the x-y plots, see below). All of these representations are interlinked -- clicking on a row in the table shows it on the image and in the plot, and clicking on an object in the image shows it in the table and in the plot, and clicking on an object in the plot shows it in the table and on the image. To see more of the columns (and see more of the options described shortly below), grab the divider(s) between the window panes and slide it to widen the catalog pane until you can see the icon that looks like this:. The table is shown exactly as it appears in the database (or as it appeared on your disk), with all columns as defined for that catalog. To understand what each column is, please see the documentation associated with that catalog (available via the catalog searching popup window shown above, or by navigating through the IRSA website.) The tab (and table) name itself is the name of the catalog file as stored on the system at IRSA; it may be a little cryptic, but the first few words should make it clear whether it is WISE, 2MASS, etc. To remove the tab, click on the blue "X". Immediately below the tab name, there are several symbols: which we now describe. The first thing to notice is that only the first 50 rows of the retrieved catalog are displayed in the table. In the example, there are 1358 sources that were retrieved as part of the search. The black arrows plus the page number allow you to navigate among these 'pages' of 50 sources each. Note that the entire set of results (not just the 50 rows you are currently viewing) can be sorted alphabetically by clicking on any column's name. (Note also that in the plotting and overlay features described below, all the sources in the catalog are plotted on the images you have, not just the 50 shown in the first page.) Spitzer Heritage Archive: Catalogs 60

62 Going from left to right along the top of the catalog tab, the next icon represents a filter: Filters are a very powerful way of exploring the catalog data, and they work the same way as they did on the Spitzer search results. Click on this icon in order to start the process of adding filters. A text entry box appears above each of the current catalog columns, with a small version of the filter icon corresponding to that row on the far left. You can type operators and values in these boxes -- hit return after typing or click in another box to implement the filter. For fields with a limited set of choices, instead of a text entry box, a filter icon will appear; click on it to select from the available choices. As an example, to show only those sources with declination above a certain value (say, 31 degrees), type "> 31" in the box above the "dec" column. Or, if you have retrieved a catalog with brightness measurements less than 6 magnitudes, find the corresponding column and type "< 6" in the form on the top of the column. After you impose a filter, then the number of rows in the catalog is restricted according to the rules you have specified, and the "filters" icon on the top right of the catalog pane has changed to remind you that there has been a filter applied, in this case just one filter: also appears after you impose filters):.. To clear the filters, click on the cancel filters icon (which Note that the filters are logically "AND"ed together -- it will impose this AND that AND this other restriction. You can relatively easily restrict things such that no data are left; if that is the case, you will get "There are no data to display." You can then cancel all the filters at once via the cancel filters icon ( ), or remove them individually by hand by editing the filter boxes at the top of each column, just as you did to impose the filters. The available logical operators are : = which means 'equal to' (exactly!), e.g., the parameter on which you are querying (the column headers as shown) is exactly equal to this value you are specifying. > which means 'greater than' < which mean 'less than'!= which means 'not equal to' (exactly!) >= which means 'greater than or equal to' <= which means 'less than or equal to' IN which means 'included within this list', e.g., the parameter on which you are querying (such as "Bandpass") is included within the list you are specifying (if the column filter is free-form text, type "value1,value2" and it will give you rows that have value1 or value2). LIKE which means 'resembles the text that is entered', e.g., the text resembles the text that you type in the box. The next icon is -- clicking on this changes the table display into a text display. The icon then changes to -- click this again to return to the default table view. The next icon is which is "Save" -- this is how you may save the whole catalog (NOTE: the WHOLE TABLE, not just the rows shown) to your own local disk. It will save it as an IPAC table file, which is basically ASCII text with headers explaining the type of data in each column, separated by vertical bars. By default, the file is called "GatorQuery.tbl" because, under the hood, the software is talking to the IRSA General Catalog Query Engine, powered by Gator. Spitzer Heritage Archive: Catalogs 61

63 The next to last option on the top of the catalog tab is this:. Clicking on this icon brings up options for the table, e.g., how many rows are displayed per page, and which columns are shown. By default, all columns are shown. The default page size is 50 rows. Note that expanding the page size to numbers much greater than 50 may result in a substantial performance degradation (e.g., your browser will appear to freeze or not appear to be doing anything while it manages and renders the large table). Note also that if you resize columns, and then go and add new columns, the original columns are resized back to their defaults after the new columns are added. Finally, when your mouse is in the catalog window pane, you see this as the last option on the top of the catalog tab:. Clicking on this expands the catalog window pane to take up the entire browser window. To return to the prior view, click on "Close" in the upper left. You can also interactively impose filters from plots you make from the catalog - see the next section for discussion. Plotting catalogs You can plot your catalog after it has loaded. The plots are another view of the catalog; by default, the catalog comes up in 'table' view, and you can swap back and forth between the 'table' and 'plot' view. After you have loaded a catalog, these icons appear in the upper right, just above the image results pane: The first one is table view, and the second is plot view. The current view is boxed in green. Click on the icon to change views. If you do not see this icon, make sure that a catalog tab is in the foreground of the target list pane. To see more of the catalog while still viewing images, click and drag the slider between the panes to enlarge the plot window pane. To obtain a full-screen view of your plot, click on the expand icon in the upper right of the window pane when your mouse is in the window:. To return to the prior view, click the "Close" arrow in the upper left. The plotting tool, by default, starts with RA and Dec plotted. Note that it does so strictly mathematically correctly -- that is, RA increases to the right (the reverse of astronomical convention). To change what is plotted, click on the gears icon in the upper left of the plot window pane:. Configuration options then appear to the left of the plot. You can choose a single column to plot against another column -- if you have loaded a WISE catalog, you could plot w1snr vs. w1mpro. You can start typing a column name into the X and Y boxes, and it will help provide you viable options from the column headings. Alternatively, you can click on the "Cols" link to bring up a pop-up window with all the columns for that catalog listed. NOTE THAT you must type in the column name exactly matching the column headings as displayed. By default, it echoes the x and y labels and units from the original table, but you can change this by clicking on the triangles below each entry box (e.g., make the label "SNR in WISE-1" rather than the more cryptic column header "w1snr"). You can also do simple mathematical manipulations. For example, you can plot w1mpro vs. w1mpro-w4mpro. However, note that as of this version, the axes are from min to max in the strict mathematical definition of the term, so in this example, the fainter W1 objects are at the top of the plot. As a workaround for this, plot -w1mpro vs. w1mpro-w4mpro to get the axes aligned in the way you are expecting such that brighter objects are at the top of the plot. Spitzer Heritage Archive: Catalogs 62

64 Note that the SEIP Source List has brightnesses measured in flux densities, so that you can plot flux densities.. or use the mathematical manipulations to convert them to magnitudes using the zero point of your choice. Note that the plot symbols are shades of grey corresponding to how many points are represented at that location in the plot. The lightest shade of grey (and smallest points) represent one point in the plot at that location, and the darkest shades of grey (and the largest points) represent many more points in the plot at that location. Put your mouse over any of the points to find out more about what is represented at that location. You can add or remove the gridlines via the "Grid" checkbox. If you have zoomed in enough such that there are just black boxes -- one object per point -- you can change the plot style such that the points are connected or unconnected. You can also restrict what data are plotted in any of several different ways. You can set limits based on the "more options" (click on the triangle next to "more options") on the lower left of the plotting window pane, or you can use a rubber band zoom, as follows. Click and drag in a sub-region of the plot. The icons in the upper right of the plot change corresponding to what you can do, in this case to these:. They are, from left to right: zoom in on the region you have selected, select the objects in the catalog, filter the catalog to leave only those objects, or expand the plot to take up the whole browser screen. If you click on the zoom icon, then the plot axes change to encompass just the sources you have selected. If you click on the select icon, then the plot symbols corresponding to your selection change shape and color, the corresponding objects overplotted on the image in the image window pane change color, and (if you change back to the table view of the catalog), the rows (corresponding to those sources) in the catalog are highlighted. If you click on the filter icon, then the catalog view is filtered down, restricted to just those sources you have selected, and the filter notes in the upper left of the plot window (and in the table view of the catalog) change to remind you that you have a filter applied. Only those sources that pass the filter are shown overlaid on the image(s). (This is the behavior of 'filter', as opposed to 'select'; the former restricts what is shown, the latter just highlights the objects.) For more on filters, see the filter section. If you move your mouse over any of the points, you will get a pop-up telling you the values corresponding to the point under your cursor. If you click on any of the points, the object(s) corresponding to that point will be highlighted in the overlays in the images shown, and highlighted in the catalog table. This works the other way too - click on a row in the catalog, or an object in the images, and the object will be highlighted in the plot or Spitzer Heritage Archive: Catalogs 63

65 the catalog or the image. If you have a very large catalog or many points in a particular location of the plot, the tool will rebin the points in the plot such that displaying the plot is faster. The plot symbols are shades of grey corresponding to how many points are represented at that location in the plot. Put your mouse over any of the points to find out more about what is represented at that location. It will tell you how many catalog rows correspond to that point, and clicking on it will highlight all of the corresponding rows in the table view and the image overlays. In order to have the tool plot one point per row, you need to zoom in or otherwise restrict the data such that there are 'few enough' points represented in the plot. If there is just one point in the plot that needs to be rebinned, all of the points will be a small point. Want to save a plot to file? At this time, the best way to do that is a screen snapshot. On a Mac, this is accomplished via holding down command, then shift, then 4, then let go and your mouse cursor changes. Hit the space bar to select the window over which your mouse is hovering. Your mouse cursor changes again, and hit the mouse button. A snapshot is then saved to your Desktop, tagged with the date and time. Once you have made an x-y plot, the plot is then effectively treated as another 'image' in the stack of images you have loaded into the program. In the Visualization section, it describes various tools, including blinking images, and removing images from the blink sequence. If, after you make a plot, you want to blink some of the FITS images, you will need to remove the plot from the image sequence, as described in the Visualization section. Examples Example: Looking for bright, red sources in a star-forming region using the SEIP source list In a star-forming region defined for this example, we are trying to find young stars. We will search in the SEIP source list. Stars without circumstellar dust should be at a variety of brightnesses, but all have infrared colors near 0. Background galaxies should be faint and red. Stars with circumstellar dust (e.g., young stars) should be bright and red. Here, we will make a plot, identify a bright and red object in the plot, and investigate its spectral energy distribution (SED). 1. Search by position from the SHA front page on IC1396. Simbad's interpretation of the coordinates are fine. Set the search radius to 0.5 deg, being sure to pick units before entering a number. Select all 7 possible search result boxes. Click Search. 2. When it comes back, you will have 7 tabs, one for each of the result boxes you checked. You may need to grab the divider between window panes and drag it to the right to see all 7 tabs. Find the Source List tab. You should have several thousand sources there, and it should be displaying the first 50 in the tab. 3. Note that all the sources (not just the first 50) are overplotted on any images you select from the Details pane, including the Super Mosaics. Go to the Super Mosaics tab, and click on any of the mosaics, and then ensure that the 'Data' tab is selected in the right "Details" pane. Note that selecting a source in the image makes its corresponding row in the catalog turn green; selecting a row in the catalog makes its corresponding source in the overplotting turn blue. (Your search target is a blue circle, the selected source in the image is a default blue square with an x in it.) 4. Ensure that you have clicked on the Source List tab in order to bring it to the foreground. In the upper right of the browser window (just above the image window pane), there is this display:. By default, the catalog is shown as a table. Click on the plot icon (far right) to view and interact with an x-y plot. It may take a few seconds to display all of the sources. Spitzer Heritage Archive: Catalogs 64

66 5. It comes up with an RA/Dec plot by default. Two things to note: (1) RA is increasing to the right, not the left, because it is plotting strictly mathematically min-to-max. (2) Each point represents more than one row of the catalog. Mouse over or click on a point to see how many rows are represented: 6. Click on the expand icon in the upper right of the plot window. Click on the one-image-at-a-time icon in the expanded view if necessary ( ). 7. Click on the gear icon in the upper left of the plot window. 8. Now, if we had magnitudes, we would plot [I1]-[I4] on the x-axis and [I1] on the y-axis. But, the source list gives us brightness measurements in flux densities. We would like to approximate what such a plot would look like, were it in magnitudes, but use the flux densities we have. Enter in the x box: log(i4_f_ap1/i1_f_ap1). This will take the log of the ratio of the aperture flux densities between I4 and I1. 9. Enter in the y box: log(i1_f_ap1) 10. Leave the "grid" box checked. 11. Click "Apply." 12. Obtain this plot: 13. Note that the points are shades of grey, denoting that at least one of the points in the plot is representative of more than one row in the catalog. 14. Click and drag from corner given approximately by (-0.25,5) to (1.25,3). 15. The icons in the upper right change after you do this, and we want to zoom on this region. Click on the magnifying glass with a "+" inside. 16. After you zoom, there should be far fewer shades of grey in the points. This means that there are far fewer points in the same location in the plots. Depending on how exactly you picked your rubber-band-zoom boundaries, your points may all be small, black squares, which denotes that every point shown is truly a single row in the catalog. 17. Find the brightest source near log(i4_f_ap1/i1_f_ap1)~0.5. Click on that point. 18. Click on "Close" in the upper left. 19. Click on the table view in the View Options:. 20. The bright, red object (I get SSTSL2 J ) is highlighted in the catalog. It should also be highlighted in the overlays on top of the image, though it may be hard to find, since the Super Mosaics come in tiles, not all of which include this source. Spitzer Heritage Archive: Catalogs 65

67 21. With this row highlighted, look for the "SED" tab in the details pane. It should look like this: Technically, yes, this is a 'flux density distribution' rather than a 'spectral energy distribution', but still, you can see the overall shape of this source's SED. Since the Source List includes JHK, WISE, as well as IRAC-1 through MIPS-24 data, all of these points are included in the SED. The W4 point is an upper limit. If you use the expand arrows in the upper right, you are given additional options where you can turn off/on individual points in the SED. Spitzer Heritage Archive: Catalogs 66

68 Data Downloads from the Spitzer Heritage Archive Contents of page/chapter: +Overview +Deciding what files to download +The Background Monitor +Help! I have a lot of zipfiles! +Using the Download Scripts +Help! These things are unzipping into separate directories! +Acknowledging Spitzer and the SHA Overview After searching and investigating your results, you have presumably decided which data to download, and the next step is actually downloading it. In the simplest case, just click the checkboxes on the far left of each row (from the AOR, Level 2, or Level 1 tabs) to pick specific data files to download, and then click "Prepare Download" to begin the packaging (and downloading) process. A pop-up window will appear in order to define exactly what kinds of data you would like to have packaged up. Clicking OK initializes this process. To select all of the data you have displayed, click on the checkbox at the top of the column of checkboxes, and all of the rows are automatically clicked (even those on subsequent pages). Then click "Prepare Download" to initiate the packaging process. From the pop-up window, you can enter an at which you would like to be notified when the packaging process is complete. (Within the same SHA session, the SHA remembers what you have entered before, but when initiating a new SHA session, you will have to re-enter this information.) The packaging process is spun off to the Background Monitor. Once the packaging is complete, to download the data, just click on the "Background Monitor" link, then click on any of the provided links reading "Download Now". Note that you control where the data are saved on your disk through your browser; your browser may be configured to store all downloads in a particular location on your disk. Deciding what files to download All users should consult the corresponding Instrument Handbook (available at the IRSA Spitzer site) for details and for information to consider for your own project. Most new users probably will want the most highly processed data versions available -- Enhanced Products first, then Level 2 (PBCD) products. More experienced users, or users wanting more control over the analysis (e.g., wanting highly accurate photometry), will want to download the Level 1 (BCD) data. Very experienced users may want the Level 0 (raw) data. Choose this option with caution! Note also that some raw data was not included in the generation of the final products. When selecting the 'raw data' download Spitzer Heritage Archive: Data Downloads 67

69 option, all of the frames associated with your AORs are downloaded, not just the ones, e.g., within a smaller search radius. The Background Monitor The Background Monitor appears in the upper right of your window to keep track of the data download. It actively changes to reflect what it is doing ("Preparing", etc.: ). A pop-up window can be called up at any time by clicking the "Background Monitor" (or "Preparing", etc.). You can watch your data being packaged, and when the data are available for download, it will update that window, providing a link (or more than one link) for downloading the packaged data. It also provides a download script (optional) if you have more than one package to download. Important note: don't log in while it is preparing a download! If you log in during a download, as far as the system is concerned, you have changed identities (from 'anonymous' to 'jones', say), and as a result it does not complete preparing the download. The Background Monitor also keeps track of very large catalog queries, ones that take a long time to render in the SHA itself. To stop any query mid-way through, click on the little red octagon ("stop sign"). If you forgot to put in your at the beginning, or if the packaging is taking longer than you expected, you can click on "Add " from the lower right of the Background Monitor popup and add your during the packaging process. Help! I have a lot of zipfiles! When downloading large quantities of data (big programs, whole campaigns, etc.), the SHA will break up the downloads into "manageable" pieces, where "manageable" is defined as "not larger than common computers and software can handle." We understand your frustration if you computer is customized to handle much larger files than the average computer. If you don't want to click to download each piece, use the download script provided by the Background Monitor, available when the packaging is complete either in the Monitor itself or from the you can arrange to have sent to you. The script can be configured to unzip the files too. See the next section for instructions on how to use it. Using the Download Scripts The Download Retrieval Script dialog gives you some options regarding which script you want to use. Generally speaking, the wget script is best for Linux and Unix users. The curl script is best for Mac users, because curl is part of the standard OS distribution; Mac users can also go retrieve and install wget and then use the wget scripts. For any of the scripts, you can also choose to include an option that unzips the zip files automatically. The files stay on disk here for at least 72 hours, so you have a window of time to download them. Save the script to a plain text file, and invoke the script. You can copy and paste the script lines individually into your terminal window, or by typing "csh [yourtextfile]" at the prompt. The files will be automatically and Spitzer Heritage Archive: Data Downloads 68

70 sequentially downloaded to your disk, and if you've selected that option, unzipped as well. For Windows users, download and save the text file of URLs. Then follow the following steps to install the wget script and then download your data: 1. Go to the Windows wget web page 2. Scroll to the Download section and retrieve the wget installation. 3. Install wget and add the binary to your path. 4. Download the text file of URLs 5. At the command prompt: wget --content-disposition -i <file_of_urls_downloaded.txt> Help! These things are unzipping into separate directories! Depending on how, exactly, you unzip your files, your computer may put the contents of each zipfile into one directory, rather than, say, the contents of each AOR into one directory (which was the original design, and the conceptually most straightforward). If you are using a GUI-based method (e.g., click to uncompress), there should be a preferences option to allow you to uncompress subsequent zipfiles into the same root directory. If you use the download script above, the flags sent on the command line that unzip the files should put all files from the same AOR in the same directory. Acknowledging Spitzer and the SHA Now that you've got your data, you're going to write a great paper. Please add this to the acknowledgments at the end (where you can include or drop the "in part" as your case applies): This work is based [in part] on observations made with the Spitzer Space Telescope, obtained from the NASA/ IPAC Infrared Science Archive, both of which are operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration. Spitzer Heritage Archive: Data Downloads 69

71 User Registration for the Spitzer Heritage Archive While you certainly do not have to register to search the archive, download data, analyze it, and write a paper, you may wish to register so that the SHA remembers you and your preferences. On the other hand, if you have proprietary data, you will need to log in so that the system grants you access to your data. If you got from the Spitzer Help Desk about account information, you may already have an account; else you can set up an account (see below). Once you have set up an account, please send us an at the Spitzer Help Desk and we'll tie your new account to your proprietary data. Note that there is a single user account/password combination for all IRSA services, but that data access, preferences, search history, data tagging, etc., are all unique to each archive. Log In The "Login" link is in the far top right of the SHA page. Select this option to log in if you know your password, or to create a new account. Create New Account Find this option by selecting "Sign in" in the far top right of the browser window, and then "Create an account" appears as an option in the lower left of the pop-up window. Select this option to create a new account. Forgot your Username or Password If you do not remember your username or password, select this option to retrieve this lost information. Find this option by selecting "Sign in" in the far top right of the browser page, and then "forgot your password?" appears as an option below the Login button. Edit Profile Find this option by logging in, and then clicking on your account name in the top right of the browser window. Then, select "Edit Profile" to change your password on an existing account. Change Password Find this option by logging in, and then clicking on your account name in the top right of the browser window. Then, select "Change Password" to change your password on an existing account. Spitzer Heritage Archive: User Registration 70

72 Update Find this option by logging in, and then clicking on your account name in the top right of the browser window. Then, select "Update " to change your on an existing account. Preferences After logging in, you also may access your preferences. First log in via the "Login" link on the far top right of the SHA page. Then find the large blue 'preferences' tab in the top center of your browser window. You can configure table page sizes, your notification , the units of a distance measurement readout, etc. To return to searching, click "Close" in the upper left. Spitzer Heritage Archive: User Registration 71

73 Quick examples for the the Spitzer Heritage Archive Very detailed step-by-step recipes for downloading data can be found at the IRSA Spitzer site, and in the Data Analysis Cookbook. There are also SHA video tutorials, including a quick start and a longer AAS-demo-style overview, available at the IRSA YouTube channel. Look for the playlist that combines all the SHA videos together. Here, we capture a few brief examples with text and screen shots. Contents of page/chapter: +I have detected an object at a non-spitzer band, and I want to know if Spitzer saw anything there. +I study {this subject, as opposed to this target}, and I want to know if there were any Spitzer programs specifically studying {this subject}. +I want to search the SHA for a whole list of objects all at once. +Quick Example: Just get my program's data out of a recent campaign. +Quick Example: Just getting calibration data. +Quick Example: Getting many zip files to automatically download +Quick Example: Finding other data that are similar to yours. +Quick Example: Finding Contributed Enhanced Product deliveries in any given region. +Quick Example: Finding data from two different instruments or modes at once. +Quick Example: Finding data from two different channels at once. +Quick Example: Finding just MIPS prime or non-prime data. +Quick Example: Filtering by PI. +Quick Example: Finding AORs that were constrained together. +Quick Example: Finding IRAC subarray Level 2 data. +Quick Example: Finding other IRAC Level 2 data that appears to be missing. +Quick Example: Downloading Raw Data. +Quick Example: Apparent logical inconsistencies in position searches. I have detected an object at a non-spitzer band, and I want to know if Spitzer saw anything there. Start an SHA search by position. Enter your desired coordinates. Ask for Level 2 and Contributed Enhanced data to be returned. Enter a search radius of at least 500 arcsec. Spitzer Heritage Archive: Examples 72

74 When you get a search result, in the search results pane, click on one of the rows you wish to investigate. Go over to the Details Pane, and click on the "AOR Footprint" tab. This is the outline of the observations. Did the field of view or the slit actually hit the specific region you wanted? Spitzer Heritage Archive: Examples 73

75 If you need to further investigate any observation, go to the Level 2 (PBCD) tab and find an image. The Level 2 tab shows you the highest-level products available for this observation, such as mosaics or extracted spectra. Look at the "file type" to discern whether they are images or tables (spectra). Click on a row corresponding to one of these products. In the Details pane, click on the "Data" tab. These are the real data that are shown. Is the object you care about within the mosaic? Can you see it? Your search position is superimposed, so you can quickly tell if there is something there. Move your mouse over the position in the image in which you are interested. Look in the upper right for a readout of the values under your cursor. Spitzer Heritage Archive: Examples 74

76 Look at the toolbox under the blue tabs for things to do with the image. Let your mouse hesitate over any of the icons for a "tool tip" indicating what it does. You can change the stretch, or rotate North-up to make it easier to investigate the image. You can use these tools to assess if the field of view or the slit actually hit the specific region you wanted, or if your object is actually in the image. If not, pick another observation and try this again until you find an observation you think would be useful to pursue further. If you have more than one observation returned, you can use the Data Coverage tab to identify the observations that you think would be most useful to further pursue. Spitzer Heritage Archive: Examples 75

77 If the data you have found are spectra, you can examine the 2-D image prior to spectral extraction to see if there is something there; you can also make line plots of extracted spectra. Convinced that you should pursue this? Go back to the AOR tab in the Results pane, and ensure that the checkbox on the far left of the line is checked. Click on "Prepare Download" (near the top of the Results pane) and ask for the Level 2 data, plus ancillary if you are feeling complete. While the data are packaging up, you may wish to see if anyone has delivered reduced data on your region back to IRSA. Click on "Spitzer Searches" (blue tab in the top left) and repeat your position search, this time ensuring that the various 'Enhanced Products' tick boxes are selected. Spitzer Heritage Archive: Examples 76

78 Enter your coordinates. This will search enhanced products from the SSC, (IRS, IRAC, and/or MIPS) as well as those delivered to the SSC and IRSA from the community. (These are currently largely -- but not entirely -- deliveries from the Spitzer Legacy Teams.) These enhanced products were generated from targets spread all over the sky, but none were all-sky surveys. You may get lucky and find some products, maybe some from bands other than Spitzer bands. USE LARGE SEARCH RADII WITH CAUTION. Some of these catalogs are very large! Additional tabs will be returned with your search results, though some may have "no data to display." Spitzer Heritage Archive: Examples 77

79 If you do find Contributed Products, click on the first link provided (the name of the dataset) to bring up another tab with the search results. You can investigate the coverage to see if you want to download the data, or overlay the source list to see if you want that catalog. You can download the data here in the same fashion as for the rest of the SHA -- click in the checkbox on the left, and 'Prepare Download' to package up the data. If you do download data or catalogs, please do obtain and read the delivery documentation (obtainable from the page you reach by clicking the 'more' link after the entry on the summary tab). There may be caveats about the images, or data quality flags in the catalogs. Spitzer Heritage Archive: Examples 78

80 You may also find other enhanced products. Click on that tab, and you can investigate the image, catalog, or spectrum in much the same fashion as elsewhere in the SHA. Please do obtain and read the documentation that goes with these products too (IRS Enhanced Product information can be found in the IRS Instrument Handbook; information about the Super Mosaics and Source List can be found as part of that delivery. By now, your original Spitzer data packaging should be done and ready for download. Click on the "Background Monitor" link in the upper right to bring up a pop-up with the packages. Spitzer Heritage Archive: Examples 79

81 Click on "Download Now" to download the files; if there are many files, try out the scripts to download them all automatically. Consult the IRAC, IRS, or MIPS Instrument Handbook for additional information about the files, descriptions of artifacts, data reduction examples, etc., and you're on your way! I study {this subject, as opposed to this target}, and I want to know if there were any Spitzer programs specifically studying {this subject}. From the main search page, pick "Abstract" to do an abstract search. If you study planetary nebulae, then a search on "planetary nebula" ought to pull up both the singular and plural forms of the noun. Note that big surveys will cover huge swaths of sky that will contain objects of many different types (e.g., many planetary nebulae in the galactic plane covered by both GLIMPSE and MIPSGAL), and this sort of search will only return projects which mentioned your search words in the abstract. However, it should give you some good leads to follow. Spitzer Heritage Archive: Examples 80

82 Click on any project to pull up all of the observations associated with that program into the Search Results window pane, and proceed from there as with any other search. Spitzer Heritage Archive: Examples 81

83 I want to search the SHA for a whole list of objects all at once. You can do a "batch search." Search by position then click on "from file." The file format can be a fully compliant IPAC table file, or a relatively simple plain text file described below. For an IPAC table file, you may find the IPAC table file verification service helpful. If doing a regular non-ipac table file search, the file format is: COORD_SYSTEM: Equatorial # Equatorial, Galactic, or Ecliptic - default is Equatorial EQUINOX: J2000 # B1950, J2000, or blank for Galactic - default is J2000 NAME-RESOLVER: NED # NED or Simbad - default is Simbad #Name RA/LON DEC/LAT PM-RA PM-DEC EPOCH "NGC 001" 12h34m23.45s 34d23m56.2s NGC d d NGC h d NGC4444 " " " " m31 legacy " " " " m32 m33 simbad NGC6946 NGC5194 ngc2992 The SHA parses on spaces, so a space is the delimiter between fields. Therefore, if there is a space in your object name (e.g., "NGC 1001" versus "NGC1001") or position (" " versus 34d23m45.45s"), you need to put quotes around the target name or its position. Note in the example above that in some cases, I have specified the epoch of the observations (e.g., "NGC3333"), or I have allowed NED to resolve the name ("m31"), or I have asked for Simbad to resolve the name ("m33"). Note that the name resolver is not case-sensitive ("NGC5194" vs. "ngc2992"). Spitzer Heritage Archive: Examples 82