a.olchevski, jinr (dubna) test beam studiesof compass ecal0 test beam studies of compass ecal0...

A.Olchevski, JINR (Dubna)

Test Beam studiesTest Beam studies of COMPASS of COMPASS ECAL0ECAL0 module module prototype with MAPD readoutprototype with MAPD readout

ECAL0 Team, JINR, DUBNA

A.Olchevski, JINR (Dubna)

Possible view of ECAL0: sizes: ~ 360x360 cm2 with central hole ~ 120x120 cm2

length: ~ 25-30 cm modules: 800 with size 12x12

cm2 (“shashlyk”) MAPDs: ~9300 (Multipixel Avalanche PhotoDiode)

for inner part: 16 MAPDs per module for outer part: 9 MAPDs per module

A.Olchevski, JINR (Dubna)

ZECOTEK: MAPD-3A 15 000/mm2

MAPD-3B 40 000/mm2

MAPD Stucture

A.Olchevski, JINR (Dubna)

Characterics of MAPD

A.Olchevski, JINR (Dubna)

• high number of pixels ~135 000 ( 3x3 mm2 )• work at low bias voltage (<70 V),• PDE ~12 %( 520 nm) (Photon Detection Efficiency)• Gain ~3x104

• Temperature dependences ~ 3%• insensitive to magnetic fields up to 15 T,• compact, rugged and show no aging*• tolerate accidental illumination• radiation hardness (>1012 p/cm2 ) *• Capacitance ~ 300pF

Problems: recovery time , temperature dependence dependence gain vs voltage Gain and PDE

* under study

Characterics of MAPD

A.Olchevski, JINR (Dubna)

3 type modules: - sampling 4mmSc/4 mm Pb, 96x96 mm2 , 36 fibers, 6ch-s (~10-11 % sampling)

- sampling 4mmSc/2 mm Pb, 12.12x12.12 cm2 , 64 fibers(32 loops), 1 tower ,4 bandles , Db = 6 mm - sampling 4mmSc/2 mm Pb, 4.04x4.04cm2 , 144 fibers(72 loops), 9 tower, Db = 6 mm (~7%)

Goals of the measurements - Resolution vs energy - Compare results with MAPD and PM - Number of photoelectrons - Temperature stabilization - Calibration by LED (monitored by pin diode) - Optimization of module structure

BEAM test at PS (T9)

A.Olchevski, JINR (Dubna)

Light guide - coneD1 / D2= 6/4.4KPM=0.54KAmpd/PM=0.6

A.Olchevski, JINR (Dubna)

Setup at Beam test atT9

A.Olchevski, JINR (Dubna)

FEE – fast preamplifier, G=14 Trigger – COMPASS( Munich, Protvino) DAQ – VME CAEN V792AC Charge ADC 32 Ch ( SADC Option)Temperature stabilization - Peltier cooler with fan (working point 15o +-0.2o)*Calibration – Led, controlled by Pin Diode

*The method of gain stabilization by using feedback with HV is possible, but noise increase with T (2 times/ 9 degree)

Read Out

A.Olchevski, JINR (Dubna)

Response 1 tower modules at 4 GeV

1 ch= 5.24 Phe 1 ch=2.00 Phe

A.Olchevski, JINR (Dubna)

Stability

A.Olchevski, JINR (Dubna)

Response vs Beam Intensity

A.Olchevski, JINR (Dubna)

Response & resolution vs Beam Energy

Response & resolution of PM Response & resolution of AMPD

Threshold estimation of AMPD 3σped =30ch-> 60 phe -> ~75 MeV

A.Olchevski, JINR (Dubna)

Response & resolution vs Beam Energy

A.Olchevski, JINR (Dubna)

A.Olchevski, JINR (Dubna)

- Long term stability - Temperature stabilization for the 9 tower module- Test with COMPASS DAQ& SADC- Tests in muon beam during the COMPASS GPD run to work in real background condition - Tests in 2009 with High Energy Beam H2. Uniformity- Continue collaboration with Zecotek firm ( increase the gain, size, PDE and decrease recovery time)

Plans

A.Olchevski, JINR (Dubna)

Acknowledgements

Appreciate very much important opportunity of T9 facility.Thanks to Lau Gatignon for very good beam quality & support.

We gratefully acknowledge the support of the Protvino and Munich  groups for presented equipment and readout electronics.

We also thank G.Mallot  and A.Magnon for help and support. Special thanks are due to V.Anosov and V. Pessaro for technical

assistance.