Multipixel Geiger mode Multipixel Geiger mode photo-sensors photo-sensors (MRS APD’s) (MRS APD’s)
Yury KudenkoYury Kudenko
ISS meeting, KEK, 25 January 2006
INR, Moscow
22
Near Detectors at 280mNear Detectors at 280m
Magnet + Side-MRD
Magnet + Side-MRD
P0D TPC TPC TPCFG
D
Pb-
P0D
EM calorimeter
EM calorimeter
EM
cal
ori
met
er
Muo
nID
hod
osco
pe
FG
D+
H2O
3m1m
1m
PMT
Iron
Tracker : SciBar type Extruded Scintillator + Wave Length Shifting Fiber
Veto all surface by plastic scintillator (Fibers goes through holes.)
3m
1m
1m
Off-axis (~2Off-axis (~2oo))
On-axis (0o)
19m
Super-K
Beam center
37m
ND280m hall
- ~ 105 WLS fiber channels- individual readout
33
Principles of MRS APD Principles of MRS APD operationoperation
Number of pixels 450 - 4000
Qpixel = Cpixel x V = Cpixel x (Vbias - Vbreakdown)Cpixel 50fmF V few volts Qpixel 2x106 electrons
Depletion region 2mDrift velosity 107 cm/sField (2-3)x105 V/cm
CPTA, Moscow (MRS APD)MePhi/PULSAR, Moscow (SiPM)Dubna
limited Geiger mode
PMT: diameter 20 mm
MRS: active area 1x1mm2
diam 1 mm
Multipixel Geiger mode APD’s invented in Russia in 1980’s
44
MRS APDMRS APD
One pixel ~ 40 x 40 m2
55
MRS APDMRS APD
New devices - Dark noise rate- PDE- Dynamic range, linearity of signal- Temperature effects- Long time stability - Lifetime - Recovery time
- Diameter of active area 1.1 mm- Number of pixels 556 - Geometrical efficiency 70-80 %- Photon detection efficiency at th=0.5 p.e. and dark rate ~1MHz 10-15% - Bias voltage range 25-75 V- Gain 106 - 107
- Sensitivity to magnetic field ( 9T) no- Cross talk 4-6%- Auto calibration and control separated p.e. peaks - Dark noise rate (th =0.5 p.e) 1 MHz
LED signal
66
1pe
2pe
3pe
Dark noise rateThreshold, p.e. Dark rate, MHz 0.5 1.0 1.5 ~0.1 2.5 0.01
Dark noise rateDark noise rate
Temperature dependence~70 – 100 kHz/deg
77
Photon detection efficiency (PDE)Photon detection efficiency (PDE)PDE=εpixel × QE × εGeiger
30-70% 60-80% 50-80%
PDE=12%
1 MHzTypical PDE ~12% (at 1 MHz (th=0,5 p.e.)New CPTA devices PDE ~15%
88
Linearity and cross talk Linearity and cross talk MRS APD, 556 pixels
The same LED signal to MRS APD and PMTthrough Y11 fiber
Crosstalk
Bias voltage = 40.0 VDark rate (0.5p.e) ~ 1MHzCrosstalk = 5-6%
99
Temperature effectsTemperature effects
PDE gradient ~ -1.8%/deg
Dark noise rate gradient ~70-90 kHz/deg
1010
Stability and lifetime study Stability and lifetime study
l.y. measurement
After temp correction
For 2 years ~150 CPTA devices are studied 3 dead
High temperature test
On-going test:10 devices are at 80 deg and HV for 15 days All OK
1111
Recovery time
t
Large pulse >600 p.e.
Dec’05 MRS #1710-002
Second pulse ~100 p.e.
First pulse:Black – 50 p.eRed - 100 p.e.Green - 300 p.e.Second: - 100 p.e.
1212
Beam test of SMRD detectorBeam test of SMRD detector
Beam test at KEK, Nov 2005. Sci/WLS/(both end MRS readout) detector1.4 GeV/c pions and protons
l.y. from one end of slab
Ped
Extruded scintillator (Vladimir, Russia)Chemical reflectorFiber KURARAY Y11, double clad, 1 mm
SMRD: about 5000 extruded scintillator slabs ~ 90 cm x 20 cm x 1.0 cm
8p.e.
1313
Beam test resultsBeam test results
S-type SMRD detector:l.y. (sum of 2 ends) 152 p.e. MIP efficiency >99%Timing at 15 p.e. ~ 1.7 ns () Space resolution ~12 cm ()
Beam scan along the slab
Time resolution
1414
Summary and outlook
Status Perspectives Diameter 1.1mm 1.1, 1.2-1.5 mmPDE 12-15% OK, R&D 20% Dark noise rate ~1 MHz (0.5 p.e.) manufacturers aim to decrease 100 kHz (1.5 p.e) OK Time resolution 1- 3 ns () with Y11 OK, both end readout to suppress noise Cross talk 4-6% OKGain 106 – 107 OK Linearity range 200 p.e. 600 pixels OK, 1000-2000 pixels 20-30 p.e. 100 pixels OK for SMRD, on-axis Long term stability ~1000 hrs, 1-2% OK, more tests Lifetime 3 of 450 are dead looks not bad, study is ongoingTemperature Dark noise rate +(70-90) kHz/deg PDE -1.8%/deg 22-25 deg OK, low temp is better Recovery time 1-5 s OK- Great progress in development of
Multi-pixel Silicon devices for last 2-3 years- Such devices are now considered as
base-line photo-sensors for the T2K near detector at 280 m