2003 TEC beam test : a quick overview

Transcription

1 2003 TEC beam test : a quick overview Presentation: A petal in the beam line! Power supplies, cooling, interlock... The available measurements. Some plots taken from the online monitoring. Post X5 studies. B.Trocme IPN Lyon 1

2 2003 TEC beam test : a quick overview(2) For more information, look at the web page: Documentation on setup (cooling) Online logbook Summary of different measurements How to analyse data Some plots taken from online monitoring Pictures 2

3 A lot of work from the whole TEC community (forgive me if I forgot someone!): Aachen I/III :B. Hegner, W. Karpinski, S. Kasselman, K. Klein, O.Pooth Antwerp: W.Beaumont Karlsruhe: V. Zhukov Louvain:O.Militaru Lyon: M.Ageron,D.Contardo, N.Lumb,S.Perries, B.Trocmé Strasbourg: R.Strub Vienna: W.Adam 3

4 The setup Petal equipped with: New ICBs. 4 R4 modules, 4 R6 modules, 2 R5 modules (1 rφ + 1 stereo). Hybrids on R1,R3,R7 (LV group I:50% of full load, II:100%,III:66%). 4

5 The setup (2) No major problem in mechanical assembly not trivial considering the variety of different pieces (bridges, washers, spacers...) 5

6 Power supply Power supplies: HV: for the 1st time,use of the floating ISEG power supplies.software control (labview). LV: Lambda power supplies. Installed in the X5 barrack 50m of MSC cables. 6

7 Cooling system Installation of the Louvain cooling plant in the X5 hall. Temperature and humidity control with probes (T:12 RH:4) Continuous dry N2 flow (at ambient temp) LV/HV interlock (Louvain software) Complete summary by Aachen group at the location: 7

8 System commissionning We faced many ring instabilities: Painful debugging due to the large amount of new hardware (long MSCables,digital optolink,icbs...). Contribution from all experts (Special thanks to Cern group:l.mirabito, P.Siegrist, R.Grabit, C.Paillard). After all,it was found that the ring is sensitive to jitter for a special data polarity (DOH to FEC). All basic tasks performed: Timing alignment Optical parameters automatic tuning (interesting behaviour at low temperature). 8

9 Available measurements Classical physic run: beam in all available modules (satisfactory functionning in all cases). several temperature conditions. HV scan. With a lead block in the beam line. 25ns beam with a special trigger configuration (ex:00100, ) APV parameters (VFS,ISHA) scan: 25ns bunched beam. Operation at optimal working point,and +/- 1 BX (study impact of previous/following events). 9

10 Available measurements(2) Pll scan (reconstruction of physical pulse shape) In the following, all plots are extracted from the online monitoring. Ongoing offline analysis by Aachen group (Vienna,Strasbourg?). 10

11 S/N for different modules 11

12 The PLL scan Principle (detailed in CMS IN 2003/021): Compute pedestals for optimal timing settings. Change pll settings (coarse delay -= 5 LHC clocks/125 ns). Acquire N events and extract number of clusters and <S/N> Change pll settings (fine delay += 5 ns),fed sampling point and go back to previous step. 12

13 Optimal working point. The PLL scan(2) 5ns difference Off time signal. S/N Nb of clusters Full efficiency 13

14 The PLL scan(3) The previous slide plots are related to R5 module: everything looks correct (including the clusters distribution see below) Strip number NB:distribution is related to cluster positions for all PLL settings! 14

15 The PLL scan : position 1 effect during beam test The position 1 is located on ring 6. Considered run:10606 (almost) off beam (scintillator) detector 15

16 The PLL scan : position 1 effect during beam test(2) Fake clusters appear for nominal setting +5,10,15ns They are mainly located in 1 st APV. 1 LHC clock Pll fine delay dependant noise? 16

17 The PLL scan : position 1 effect during beam test(3) Similar effects: seen in positions 2,4 and 5 restricted to one strip (clusters always at the same position!). 17

18 The PLL scan : position 1 effect in lab Effect reproduced afterwards at Lyon with identical setup (except: HV PS, long MSC, long digital link, cooling plant). Nb of clusters vs time PLL fine delay = 12 (NB:here 1 ns steps 5 ns at X5) Identical plot with different initial PLL settings(ex:fine delay =12)! 18

19 The PLL scan : position 1 effect in lab(2) Origin: drift of the pedestal when pll fine delay is changed! Fine delay=0 Fine delay=12 Strip by strip differences can reach 10 ADC counts fake clusters in a specific region (pll scan:when pll settings are changed,pedestal are NOT recomputed!). 19

20 Position 1 effect: further studies in lab Effect remains when: Changing the module in the position 1. Removing physically all modules and hybrids. Replacing the ring internal lines (DOH to CCU1, CCU1 to CCU2, CCU2 to DOH) by external cables. Trigger frequency is changed. A single detector is placed on a bare ICB (without other ICBs and petal structure).moreover effect seems to be enhanced (all APVs affected!) 20

21 Position 1 effect:further studies in lab(2) Effect disappeared when replacing the detector by a bare hybrid. Effect amplitude is drastically reduced when placing a grounded Cu shielding in between the module and the interconnect board. ~20 times less fake clusters Effect disappeared when putting detector perpendicular (!) wrt the petal. 21

22 Position 1 effect : other symptoms Noises with HV on (left) and off(right) Top:regular position Bottom:vertical position 22

23 Nota bene The pll scan routine has already been used during august beam test with an old ICB: No hint of a problem. Confirmed by yesterday experiment in lab! 23

24 Preliminary conclusions: When changing pll settings, a drift of pedestal line of the detector in position 1 is observed. This is correlated with a distorted noise. This effect seems to have a magnetic origin. It does not exist on old design ICB. It does not exist with a bare hybrid. Ongoing work. 24

25 Beam test achievements: Conclusions Petal with almost final mechanic in a beam line. No specific problem in power supply (high LV load,msc...) Efficient slow control+interlock system. High DAQ efficiency. A lot of data to analyse (volunteers are welcome!!). Satisfying performances with a double sided module and with cooled modules (cooling however need further investigations). Ongoing studies on: Pll scan effect. 25