Y. Zhao

New prototype multi-gap resistive plate chambers with long strips

A new kind of Multi-gap Resistive Plate Chamber (MRPC) has been built for the large-area Muon Telescope Detector (MTD) for the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). These long read-out strip Multi-gap Resistive Plate Chambers (LMRPCs) have an active area of 87.0 � 17.0 cm 2 and ten 250mm-thick gas gaps arranged as a double stack. Each read-out strip is 2.5 cm wide and 90 cm long. The signals are read-out at both ends of each strip. Cosmic ray tests indicate a time resolution of � 70 ps and a detection efficiency of greater than 95%. Beam tests performed at T963 at Fermilab indicate a time resolution of 60–70 ps and a spatial resolution of � 1 cm along the strip direction. & 2008 Elsevier B.V. All rights reserved.

Performance of multigap resistive plate chamber in a γ-ray aging test

The aging test of multigap resistive chamber (MRPC) was carried out under conditions of irradiation from a 137Cs γ source facility. The total charge induced at the anode or at the cathode of the MRPC module was about 29 mC. The gamma dose rate was 10−2 Gy·h−1, and the total accumulative radiation dose was 4.3 Gy. After irradiation, there was an obvious degradation in the properties of the MRPC module.