MCP-PMT status. Samo Korpar. University of Maribor and Jožef Stefan Institute, Ljubljana Super KEKB - 3st Open Meeting, 7-9 July 2009

Transcription

1 , Ljubljana, 7-9 July 2009 Outline: MCP aging waveform readout (MPPC) summary (slide 1)

2 Aging preliminary news from Photonis Old information: Current performance (no Al protection layer): 50% drop of efficiency after 10-15C/tube = mC/cm2 Expect ~ 10 mc/cm2/year(?? window photons x3) on ARICH (scaling the TOP estimate) expect to improve the ageing by a factor > 5 (use a different scrubbbing technique, deep UV electrons) New aging test preliminary: 250 mc/cm2 accumulated drop in radiant sensitivity (blue) ~10% (slide 2)

3 Aging setup - IJS XY stages NA MM-4M Reference PMT HPK R1463 shielding wall MCP LED ~470nm Beam collimator Light tight box Beam expander Optical fiber Ortec FTA-820 A=200 Ortec FTA-820 A=200 CaenV814 discr. CaenV965 QDC CaenV830 scaler. TRG (slide 3) ALS 635nm 10kHz Monochromator SP-2155 PI-Acton

4 PDE monitoring PDE measured regularily (every 200mC/cm2): by using a monochromator (deuterium and tungsten lamp) normalized relative to a calibated PMT measured at the centers of monitored channels initial test (tungsten): first check at 200 mc/cm2 (today) (slide 4)

5 Current and rate monitoring Total current and rate on monitored chanels measured every minute. daily variation with teperature similar variation on reference PMT (slide 5)

6 Gain monitoring anode current 3μA No illumination Initial gain at HV = -2200V ~3 x 105 Gain drop at high rate operation Monitor average pulse height (slide 6)

7 Accumulated charge (slide 7)

8 Ruben Verheyden Waveform readout MPPC Single photon detection and precise timing Compare different Hamamatsu MPPC's: 3x3 mm; 100 μm pitch; model S P(X); Serial # 19; Vop = V 1x1 mm; 25 μm pitch; model S C; Serial # 34; Vop = V 1x1 mm; 100 μm pitch; model TBD; Serial # TBD; Vop = N / A Compare different operating Voltages Compare different light intensities (Filters 6.25%; 12.5%; 50%) Setup: Laser, filters, diffuser small # of photons hit MPPC TARGET for readout fast amplifier (μpc2710tb) ( + Attenuator + Ortec fast amplifier for the 3x3 mm MPPC) (slide 8)

9 more light 3x3 mm MPPC, S P(X): Photon Spectra higher bias voltage (slide 9)

10 more light 3x3 mm MPPC, S P(X): TDC vs. ADC higher bias voltage (slide 10)

11 more light 3x3 mm MPPC, S P(X): Rough Timing higher bias voltage (slide 11)

12 random photons added 1x1 mm MPPC, S C: Photon Spectra higher bias voltage (slide 12)

13 random photons added 1x1 mm MPPC, S C: TDC vs. ADC higher bias voltage (slide 13)

14 random photons added 1x1 mm MPPC, S C: Rough Timing higher bias voltage (slide 14)

15 Extracted Timing 3x3 MPPC 3x3 mm SiPM > S P(X) Timing [ns] Vop st 1 peak 2 nd peak x1 MPPC Vop 70, ,3 71,6 71,7 1st peak 0,378 0,333 0,323 0,318 0,305 1x1 mm SiPM > S C no noise noisy Timing [ns] Timing [ns] rd nd st 3 peak 3rd peak 2 peak 1 peak 2nd peak 0,276 0,273 0,458 0,342 0,324 0,282 0,279 0,449 0,500 N/A 0,291 0,259 0,510 0,466 N/A 0,315 0,284 0,412 0,404 N/A 0,326 0,348 0,389 0,384 N/A (slide 15)

16 Summary and plan Aging: accumulated total anode charge ~200mC/cm2 will be reached today change in performance on the order of 10% - to be checked PDE will be measured every 200 mc/cm2 (first measurement today) Waveform electronics: currently testing with MPPCs timing and charge can be measured test with MCP-PMT after finishing MPPC tests (slide 16)

17 BACKUP SLIDES (slide 17)

18 Aging test (slide 18)

19 Aging test SETUP: monochromator 200nm-900nm laser source: 400nm,630nm LED for aging (blue ~470nm) reference PMT for QE monitoring PMT current monitoring DAQ with scalers and ADC Start aging test end of March (slide 19)

20 MCP out timing 1 Rok Dolenec (slide 20)

21 MCP out timing 2 Rok Dolenec (slide 21)

22 MCP out timing 3 Rok Dolenec (slide 22)

23 MCP out timing 4 Rok Dolenec (slide 23)

24 MCP out timing 5 Rok Dolenec (slide 24)

25 MCP out timing 6 Rok Dolenec (slide 25)

26 Waveform readout 1 Ruben Verheyden (slide 26)

27 Waveform readout 2 Ruben Verheyden (slide 27)

28 Waveform readout 3 Ruben Verheyden (slide 28)

29 Photon detector summary Many tests have been performed since last meeting: magnetic field test of HAPD, MCP-PMT and MPPC all perform well - some properties improve beam test of MPPC module in 120 GeV muon test beam at CERN accelerated aging test of HAPD (@ Hamamatsu) measurement of neutron fluencies in Belle tests of new ASIC generation To do list: aging and long term stability test of HAPD and MCP-PMT check possible improvements in photon detection efficiency of HAPD and MCP-PMT electronics - test detectors with WFS and new ASIC test of MCP-PMT timing properties in magnetic field check the timing capabilities of HAPD Decision on photon detector technology March meeting (slide 29)

30 HAPD MCP-PMT MPPC Nph 7 ( 14) 10 ( 15) 30 σϑ B = 1.5T OK (improved perf.) OK (improved perf.) OK long term stab. (aging) OK (HV stability?) OK? OK OK(?) X 2y < 1000? < < 4000 < 20 WFS WFS ~ 60k? ~ 120k? leakage current? signal / noise production 2.5 y pieces < 600 cost / < 7000 piece electronic ASIC s channels ~ 75k material? neutron damage (slide 30)

31 Photon detector candidate: MCP-PMT Model 85015/A1 (old sample ): two MCP steps - chevron configuration 64 (8x8) anode mm, gap ~ 0.5mm bialkali photocathode gain ~ 0.6 x 106 (@2400V) 10µm (25µm) pores open area ratio ~ 70 % (60 %) size ~ 59mm (71mm) effective area fraction ~ 80% (52%) excellent timing < 40ps (50ps) - single photon K-MCP 4.4mm (6.1mm), MCP-A 3.7mm (5.2mm) window thickness 1.5mm (2mm) MCP-PMT multi-anode PMTs σϑ~15 mrad (single photon) number of hits per track N ~ 10 σ ~ 4.7 mrad (per track) ϑ BURLE ~ 5 σ π/k separation at 4 GeV/c (slide 31) Tested in combination with multi-anode PMTs

32 Tests in magnetic field: ADC vs B HV = 2500 V B = 1.5 T gain drop observed in magnetic field 1.5T increase HV for ~200V to reach the same amplification as in B=0T single photon ADC distribution measured in magnetic field gain as a function of magnetic field for different operation voltages. (slide 32)

33 Tests in magnetic field: charge sharing Number of detected hits on individual channels as a function of light spot position. HV = 2400 V B = 0 T HV = 2500 V B = 1.5 T Reduced effects of charge sharing and photo-electron backscattering are (slide 33)

34 Tiling scheme Number of MCP-PMTs and covered area fraction ring # PMTs fraction % % % % % % % % % % % all % Total number <1000 and rough estimate for price < 4M (uper limit) (slide 34)

35 Additional feature: RICH+TOF Make use of fast photon detectors: measure time-of-flight with Cherenkov photons from PMT window and aerogel START Beam test: 50ps per single photon (~20ps per track) Cherenkov photons from aerogel STOP track Cherenkov photons from PMT window aerogel MCP-PMT ~35ps per track Cherenkov photons from the window can be used to positively identifiy particles below the threshold in aerogel (slide 35)

36 TOF capability Using Cherenkov photons emitted in the PMT window (n~1.46) PID can be extended into the lower momentum region: Kaons and protons can be positively identified below the Cherenkov threshold in aerogel (n~1.05). π K p 2GeV/c π/k: t ~ 180ps Cherenkov angle in aerogel (n=1.05) for pion, kaon and proton. 4GeV/c π/k: t ~ 45ps Time-of-flight difference for pions and kaons from IP to forward PID (2m). (slide 36)