Towards a large-area RPWELL detector: design optimization and performance

Abstract

We present a new design and assembly procedure of a large-area gas-avalanche Resistive-Plate WELL (RPWELL) detector. A 50 × 50 cm2 prototype was tested in 80 GeV/c muon beam at CERN-SPS, presenting improved performances compared to previous ones: MIP detection efficiency over 96% with 3% uniformity across the entire detector area, a charge gain of ≈ 7.5 × 103 with a uniformity of 22%, and discharge probability below 10-6 with a few single hotspots attributed to production imperfections. These results pave the way towards further up-scaling detectors of this kind.