Test for YBJ-ARGO RPC working in avalanche mode

The measurement of YBJ-ARGO Resistive Plate Chamber (RPC), working in avalanche mode was performed. With different component of i-C4H10 in C2H2F4-based gas mixtures C2H2F4/i-C4H10/SF6, the behavior of the detector with respect to the high voltage was studied. The experiment confirms that it is possible to operate YBJ-ARGO RPC in avalanche mode. The results show that with the gas mixtures containing 10% of i-C4H10 the detector achieves its optimum performance.