A Large-Area Timing RPC

A large-area Resistive Plate Chamber (RPC) with a total active surface of 160×10 cm was built and tested. The surface was segmented into two 5-cm wide strips readout on both ends with customized, very high speed, front-end electronics. A timing resolution σ = 50-75 ps, with an efficiency for Minimum Ionizing Particles (MIPs) larger than 95%, was attained over the whole active area, in addition to the position resolution along the strips of 1.2 cm. Despite the large active area per electronic channel, the observed timing resolution is remarkably close to the one previously obtained (σ = 50 ps) with much smaller chambers of about 10 cm area. These results open the perspective of extending the application of timing RPCs to large-area arrays exposed to moderate particle multiplicities, where the low cost, good time resolution, insensitivity to the magnetic field, and compact mechanics may be attractive when compared with the standard scintillator-based Time-of-Flight (TOF) technology.