Status and Plans for APS Testing B Adams, A Elagin, R Obaid, S Vostrikov, M Wetstein

Transcription

1 University of Chicago Status and Plans for APS Testing B Adams, A Elagin, R Obaid, S Vostrikov, M Wetstein Tuesday Meeting July 16, 2012

2 8 Test-Chamber: Goals 8 - Goals First tests of 8 MCPs Characterize gain and timing characteristics Optimize operational voltages Test LAPPD anodes in a working context Develop hit reconstruction algorithms Test PSEC4 electronics. 2

3 8 Test-Chamber: A Short History 8 - History First tests of 8 MCPs Characterize gain and timing characteristics Optimize operational voltages Test LAPPD anodes in a working context Develop hit reconstruction algorithms Test PSEC4 electronics. Observation of first pulses Systematic tests with 40 strip anode Systematic tests with 30 strip anode Yesterday, we finished taking our final set of data for this 30-strip anode test. In order to better focus on systems-integration issues, future 8 testing will happen through the demountable. These 30 strip data comprise what we believe to be publicationworthy data on the timing properties of 8 LAPPDs 3

4 8 Test-Chamber: Data Sets 8 - Data Sets Data for QE calibration Position scans along stripline Single PE Multiple PE Multi-PE scan in the direction perpendicular to striplines High stats single and multi-pe data for constructing best TTS measurements Voltage scan to optimize timing Single PE Multiple PE 2D scan - 3 strips (one-side) and external trigger 2D scan - 2-sides of central strip + 2 neighbors - self triggering All data have been converted to our matlab format (L0). ~50% have been fully processed. ~25% have been looked at. 4

5 Factors That Determine Time Resolution 8 - Selected Results At the Front End: Sampling rate (f s ) Nyquist-Shannon Condition Analog bandwidth (f 3DB ) Noise-to-signal (!u/u) credit: Stafan Ritt (Paul Scherrer Institute) B Adams (APS-ANL), M Chollet (APS-ANL), A Elagin (Uo!C/ANL), R Obaid (UofC), A Vostrikov (UofC), M Wetstein (UofC/ANL) Intrinsic to the MCP: Operational voltages Gain Geometry Pore size Continuous vs discrete dynode 5

6 Time Resolution - Last Week 8 - Selected Results 4253 pulses 2843 pulses Best timing measurement: Most pulses have an RMS aound 38 picoseconds Some pulses (with broad rising edges and more signal on the neighboring strips) have an RMS around 100 picoseconds. Working on understanding these data 6

7 Time Resolution - Quality Cuts 8 - Selected Results Charge on central strip/charge on neighbors risetime Charge on central strip/charge on neighbors centroid We!ve identified the events with bad timing. Don!t know what they are, but we can clearly separate them. We!re working on this. 7

8 Time Resolution (with cuts) 8 - Selected Results Single PE time resolution for economical, large-area anode: ~63 psec multi PE time resolution for economical, large-area anode: ~56 psec 8

9 8 - Selected Results Timing and Gain Single PE PHD: 2e7 peak multi PE PHD: 2e7 peak - must be mostly singles 2 pe peak? (Higgs!?) 9

10 Status and Next Steps Status and Next Steps Wednesday - Turn off and remove 8 chamber Final demountable leak-check (already sealed and baking) Move demountable to laser table Set up optics New enclosure Thurs/Fri - Voltage tests Signal? Mon/Tues - Electronics integration Begin systematic testing Look for ground loops 10