Uniformity study of large size glass RPC detector using an alternative front-end electronics for INO-ICAL experiment

摘要

The proposed INO-ICAL experiment is planning to use large size RPC chambers as active detector element. Besides handling and operating issues for such large size detectors, uniformity of their response is going to be another challenge. Only a few works were dedicated to study this feature. We report on the study conducted to analyse the response uniformity of a large size 1 m × 1 m RPC prototype detector working in avalanche mode with a gas mixture of 94.5% R134a, 5% iso-butane and 0.5% sulphur hexafluoride. The cluster size, efficiency and count rate have been studied on the whole RPC chamber using cosmic rays for assessing the uniformity of the chamber and to spot any edge effects eventually. To perform this study we use a readout system based on the HARDROC ASIC. The latter with its 64 channels each equipped with a circuit made of preamplifier, fast shapers and discriminators to read out the RPC fast signal.