Visualization-directed interactive model-fitting to spectral data cubes CRICOS provider 00111D

Transcription

1 Visualization-directed interactive model-fitting to spectral data cubes CRICOS provider 00111D Christopher Fluke with Jayanne English (U. Manitoba) David Barnes (Swin) Ben Barsdell (Swin), Amr Hassan (Swin) AstroMed09: Sydney

2 Overview What are spectral data cubes? [also talk by Amr Hassan] Why are they (potentially) difficult to understand? Spatial space versus Spectral space The role of (interactive) visualization in developing intuition S2PLOT: programming library for interactive 3D graphics Application demonstration Quantitative analysis: 3D Cartesian Shapelets Summary AstroMed09 Visualization-Directed Interactive Model Fitting 2

3 Spectral Data Cube: Definition Dimensions: 2 spatial + 1 spectral (Often) Gridded data: (x, y, ) or (x, y, ) (x, y, v los ) Observed Emitted AstroMed09 Visualization-Directed Interactive Model Fitting 3

4 Sources of Spectral Data Cubes Radio telescope Aperture synthesis Mosaic Multibeam Optical/IR Scanning Fabry-Perot Scanning long slit Integral field units (Multi-object spectrographs) Swinburne Astronomy Productions AstroMed09 Visualization-Directed Interactive Model Fitting 4

5 Medicine: 3D Structure = 3D Structure AstroMed09 Visualization-Directed Interactive Model Fitting 5

6 Simulation to Spectral Cube John Hibbard (NRAO) Image John Hibbard (June 2008) 6-d model space Space: (x,y,z) Velocity: (v x,v y,v z ) 3-d observation space Space: (x, y) Line-of-sight velocity: (v los ) AstroMed09 Visualization-Directed Interactive Model Fitting 6

7 Automated Approaches M83: Rogstad et al. (1974) Figure 8: 3D Model Figure 9: Projected on sky Figure 10: HI map Differentially rotating HI disks e.g. Rogstad et al. (1974); Begeman (1989) 4 parameters: V sys, V circ, i, ϕ as function of radius Standard technique for simple models Increasing complexity: Warps? Anomalous gas? Mergers? AstroMed09 Visualization-Directed Interactive Model Fitting 7

8 Local Volume HI Survey Intensity Velocity AstroMed09 Visualization-Directed Interactive Model Fitting 8

9 Visualization-directed Approach From Canadian Galactic Plane Survey/DRAO. Courtesy J.English Build and visualize interactive models to enhance intuition and enable fitting and analysis of complex kinematical structures from spectral data cubes AstroMed09 Visualization-Directed Interactive Model Fitting 9

10 Computation 6-d model space Camera projection from orientation (x,y) preserved 3-d observation space Calculate v los from v = (v x, v y, v z ) Add to spectral cube voxel AstroMed09 Visualization-Directed Interactive Model Fitting 10

11 Technical Requirements Interactive frame-rates Real-time updates Handle simulation and data Volume rendering and isosurfaces Support stereoscopic displays Support 3D publication Simple application development AstroMed09 Visualization-Directed Interactive Model Fitting 11

12 S2PLOT: Interactive 3-d graphics library AIM to enable visualization-led scientific discovery BY making an easy-to-use programming library THAT WORKS ON the astronomer s desktop workstation AND WITHOUT RECOMPILATION ON advanced display devices RESULT S2PLOT: Barnes et al., 2006, PASA, 23, 82 V2.6 source code via Google Group ADASS 2009 Visualization-Directed Interactive Model Fitting 12

13 S2PLOT: A library for Visualization-led scientific discovery Programming library C/C++, Fortran (and Python) Static and dynamic data Real-time interaction Mouse + keyboard navigation Runs on Apple/OSX, GNU/Linux Standard and enhanced displays 3D-PDF support built in (VRML) AstroMed09 Visualization-Directed Interactive Model Fitting 13

14 Enhanced displays + Enhanced interaction Zalman Trimon 2D/3D Display Remote control for S2PLOT iphone SDK User programmable ADASS 2009 Visualization-Directed Interactive Model Fitting 14

15 3D-PDF Support ADASS 2009 Visualization-Directed Interactive Model Fitting 15

16 Biomedical Applications Impact of Nanoscale Roughness of Titanium Thin Film Surfaces on Bacterial Retention Ivanonva, E.,, Fluke, C.J., Barnes, D.G., et al. (2009), Langmuir Atomic Force Microscopy of titanium surfaces of increasing roughness: 3nm, 12nm, 150nm AstroMed09 Visualization-Directed Interactive Model Fitting 16

17 3D PDF: S2PLOT to Acrobat 3D via VRML Shift-w Add S2PLOT JavaScript Convert TGA textures to PNG textures ADASS 2009 Visualization-Directed Interactive Model Fitting 17

18 S2PLOT Elements Handles: cs2hcb() Screen: ss2tsc() Camera: ss2qc() Isosurface: ns2cis(), ns2dis() Volume Render: ns2cvr(), ds2dvr() Points: ns2point() Panels: xs2mp(), xs2ap(), xs2pp() Coordinates: s2box() Callbacks: cs2scb () Text: s2textxy() Draggable Handles: ds2ah(), cs2sdhcb() Lines: ns2line() AstroMed09 Visualization-Directed Interactive Model Fitting 18

19 Model Elements, Controls and Tools Required enhancements: Interactive Rotation curve Interactive Density profile Models: Rotating disks Expanding shell N-body galaxies (Gadget) Realistic Noise! Warps Hot spots Jets Quantitative tools: 3-d Cartesian Shapelets AstroMed09 Visualization-Directed Interactive Model Fitting 19

20 Cartesian Shapelets: Refregier (2003) B 0 B B B 3 B B Figure courtesy: Adrian Malec (Swinburne) AstroMed09 Visualization-Directed Interactive Model Fitting 20

21 2-D Shapelet Reconstruction Figure courtesy: Adrian Malec (Swinburne) Original Image Image simulation (Massey et al. 2004; Ferry et al. 2008) Morphological classification (Kelly & McKay 2004; Young et al. 2005) Weak lensing (Refregier & Bacon 2003; Kuijken 2006; Massey et al. 2007) AstroMed09 Visualization-Directed Interactive Model Fitting 21

22 3-d Cartesian Shapelets (Fluke, Malec, Barsdell, et al. in prep) ϕ 3,(000) ϕ 3,(010) ϕ 3,(202) ϕ 3,(124) AstroMed09 Visualization-Directed Interactive Model Fitting 22

23 Analytic Expressions (Fluke et al. in prep) Mass Centroid AstroMed09 Visualization-Directed Interactive Model Fitting 23

24 3D Cartesian Shapelets Input Model Reconstruction (GPU!!) Residual AstroMed09 Visualization-Directed Interactive Model Fitting 24

25 Next steps Visualization (Amr Hassan) S2PLOT prototype - only suitable for small cubes Integrate with GPU volume rendering framework General-Purpose GPU Computing Real-time model fitting Advantages in using GPU = highly parallel computation AstroMed09 Visualization-Directed Interactive Model Fitting 25

26 Summary Data Knowledge Discovery Characterise Data Isolate regions Identify velocity ranges Choose resolution Noise properties Generate Model Simple components N-body simulations Tools/Controls Modification history Shapelet model Compare with Data Virtual observation Add noise Residual map Qualitative Quantitative S2PLOT: real-time, interactive, 3-d Publish via 3d-PDF S2SLIDES: Presentation Stereoscopic Displays AstroMed09 Visualization-Directed Interactive Model Fitting 26