High-rate timing resistive plate chambers with ceramic electrodes

Abstract We describe recent advances in developing radiation-hard ceramic resistive plate chambers (CRPCs) with Si 3 N 4 /SiC composites. Bulk resistivity measurements for this material for different manufacturing processes are reported. The results show that the bulk resistivity ρ can vary between 10 7 and 10 13 Ω cm . The varistor type behaviour of the material is analysed. A comparison with other materials used in timing RPCs is given. We describe the assembly and tests of CRPC prototypes in electron and proton beams. For a prototype with ρ ~ 5 × 10 9 Ω cm , the efficiency of the detectors is 95% at a flux of 2 × 10 5 cm − 2 s − 1 . The time resolution at the same flux is about 120 ps. A prototype with ρ ~ 2 × 10 10 Ω cm shows an efficiency of about 85% up to fluxes of 5 × 10 4 cm − 2 s − 1 with a time resolution better than 80 ps. The results are compared with RPC models.