Scattered Proton Detection System for Σp Scattering Experiment with the Cylindrical Scintillating Fiber Tracker and BGO Calorimeters

The scattered proton detection system CATCH is under construction for the Σp scattering experiment at J-PARC (J-PARC E40). CATCH is composed of a cylindrical scintillating fiber tracker (CFT) and BGO calorimeters. We performed a test experiment at the Cyclotron and Radioisotope Center in Tohoku University to evaluate the CFT performance. We obtained an energy resolution of scintillating fibers as (14.29 ± 0.14)% at an energy deposit of 1.5 MeV and proton-hit detection efficiency of CFT as (97.30 ± 0.02) and (87.63 ± 0.04)% for UV and Φ layer, respectively.