160 likes | 254 Views
Last results from test of timing glass RPC with strip readout. IHEP+JINR. 2 nd PANDA Russia Workshop, 27 April 2010. A little bit of history about JINR+IHEP efforts. /. The PANDA Workshop, ITEP MOSCOW, April 17-18 2008. 11-14 identical MRPCs. Strips with double ended readout.
E N D
Last results from test of timing glass RPC with strip readout IHEP+JINR 2nd PANDA Russia Workshop, 27 April 2010
/ The PANDA Workshop, ITEP MOSCOW, April 17-18 2008
The PANDA Workshop, ITEP MOSCOW, April 17-18 2008 • 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.
4 gap glass RPC inside The PANDA Workshop, ITEP MOSCOW, April 17-18 2008
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 % Thickness of six-gap RPC made of 0.6 mm glass plates
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
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
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
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 very preliminary 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