Simulation study of the relation between MRPC - Performances and working gas

With an excellent time resolution, the Multi-gap Resistive Plate Chamber (MRPC) has been applied as TOF detector in particle physics experiments. We constructed more than 30 MRPC modules that were set up on the tray of RICH-STAR successfully. By the program of Magboltz, the parameters of working gases in MRPC were calculated. Based on the detector physics the relation between MRPC performance and working gas was analyzed, which is helpful to optimize the proportion of gas mixtures for RPC and MRPC.