RPC with strip readout Last results from test of timing glass IHEP+JINR 2nd PANDA Russia Workshop, 27 April 2010

A little bit of history about JINR+IHEP efforts

The PANDA Workshop, ITEP MOSCOW, April 17-18 2008 / The PANDA Workshop, ITEP MOSCOW, April 17-18 2008

Strips with double ended readout. Strip length ~30 cm 11-14 identical MRPCs. Strips with double ended readout. Strip length ~30 cm If strip width is 3 cm, one module contains 64 strips. Total active area ~ 6.4 m2. Signal is amplified and digitized at RPC. The PANDA Workshop, ITEP MOSCOW, April 17-18 2008

The PANDA Workshop, ITEP MOSCOW, April 17-18 2008 4 gap glass RPC inside The PANDA Workshop, ITEP MOSCOW, April 17-18 2008

Thickness of six-gap RPC made of 0.6 mm glass plates material X0(mm)‏ thickness (mm)‏ X/X0 (%)‏ glass 127 8x0.6 3.83 aluminium 89 2x1 2.22 copper 14.4 0.1 0.69 mylar 287 0.6 0.21 kapton 286 0.25 ~0.10 SUM ~ 7 % 6 6 6

6 gap RPC prototype tested with beam at IHEP

RPC resolution and efficiency vs. applied voltage HV=9kV, time resolution ~45ps, efficiency above 98% Time-charge correction RPC+”RPC FEE1” developed for FOPI RPC Jülich, XXX PANDA meeting, 2009 8 8 8

Main results from test done in2008 Very first steps have been done. Time resolution of ~50 ps can be obtained with 6-gap glass MRPC having strips with width of 25mm. Neither efficiency nor resolution depends on position along strip. With double end readout a spatial resolution along a strip is not worse than 1 cm. If a coordinate along strip is known (say, from a tracker) a one-end strip readout is enough to provide with good timing resolution. Number of readout channels in this case can be reduced by 2. Jülich, XXX PANDA meeting, 2009 9 9 9

TIME-OVER-THRESHOLD METHOD. BEAM TEST OF 6 GAP RPC. TIME-OVER-THRESHOLD METHOD. 2009: RPC+NINO(ALICE)+HPTDC(100psec/count, Dubna) 2010: RPC+TRB-HADES (improved TOT + 100psec HPTDC) 2nd PANDA Russia Workshop, 27 April 2010

2009: ENDS OF A STRIP ARE NOT LOADED WITH RESISTORS time width Multiple reflections width 2nd PANDA Russia Workshop, 27 April 2010

2009: RESISTOR AT END OF A STRIP MATCHES THE IMPEDANCE OF THE TRANSMISSION LINE. time width Two ends of the same strip width 2nd PANDA Russia Workshop, 27 April 2010

Time-width correction for the slewing time 2009: RESISTOR AT END OF STRIP IS TAKEN IN CORRESPONDANCE WITH THE IMPEDANCE OF STRIP LINE. Time-width correction for the slewing time width Final result: after subtraction of trigger jitter the resolution is σ ≈ 120 psec 2nd PANDA Russia Workshop, 27 April 2010

2010: RPC+TRB_HADES Resolution vs HV very preliminary Efficiency vs HV 2nd PANDA Russia Workshop, 27 April 2010

WE DO NOT UNDERSTAND HOW HPTDCs WORK !!! Tests of HPTDC with a pulser: time jitter of measured signal dependently to delay between signal and “common stop” HPTDC from Dubna HPTDC from HADES 2nd PANDA Russia Workshop, 27 April 2010