Test of BESIII RPC in the avalanche mode

The installation of the BESIII RPC system has been completed. Cosmic ray test results show that they perform very well in streamer mode and meet the BESIII requirements. We have tested several RPCs in the avalanche mode with the addition of extra SF6 in the gas mixture. We find an efficiency plateau that reaches ~95%, and a time resolution of 1.8 ns. This demonstrates that the BESIII-type RPC can work in the avalanche mode as well.