Quenching properties of gas mixture in glass RPC operated with streamer mode

Quenching properties of gas mixture in a resistive plate chamber operated with streamer mode were investigated using optical image taken by the CCD camera and signal pulse waveform recorded by the digital oscilloscope. We have tested four quenching gases: C 2 H 2 F 4 , C 2 F 6 , CBrF 3 and SF 6 . Streamer size, brightness and induced charge linearly depend on the ratio of Ar to quenching gas and their slopes are a function of electron affinity for each quenching gas.