A new design of MRPC to reduce noise and crosstalk

Abstract

The CBM time of flight wall is proposed to be built with MRPC technology. In the past few years we have successfuly improved the rate capability of MRPCs to CBM level. However, in a relative high particle multiplicity situation (over 20 kHz/cm2), multi-hit capability is one of the most demanding requirement of the detector. In a free running mode too many noise not only affect the performance of MRPC but also enlarge the data file or even damage the FIFO. So it is needed to develop low crosstalk and low noise MRPC to meet CBM-TOF requirement. Three strip-readout MRPC with or without shielding grounds were designed to study how to reduce noise and crosstalk of MRPCs. In this paper we report on the performance of three different structures of MRPCs named G-0, G-2 and G-3. Tests with cosmic rays were performed at Tsinghua University. The results show that MRPC G-2 can perform better than other two structures, the average cluster size of G-2 is lower than 1.28 strips and the noise level is below 0.5 Hz/cm2. The detection efficiency is over 98% and the time resolution is around 65 ps.