Charge Threshold Study of a Glass RPC in Avalanche Mode

India-based Neutrino Observatory (INO) is proposed to detect atmospheric neutrinos and measure the earth’s matter effect to address the mass hierarchy problem in neutrino physics. INO is going to host the world’s largest 50 kton iron calorimeter (ICAL) using 28,800 Resistive Plate Chambers (RPC) as an active element. These glass RPCs are very efficient for the energy of coming muons on the GeV scale. The performance of the RPC depends on how we are separating the signal from the background. We are studying the performance of a glass RPC of dimension 30 × 30 cm2 by measuring the efficiency of RPC and calculating charge and timing of signal with varying charge threshold at flow rate 10 standard cubic centimeters per minute (SCCM) of gas mixture C2H2F4 / iC4H10 / SF6 at 10.4 kV and 21∘ C with relative humidity (RH) ∼ 53%.