Construction and performance test of charged particle detector array for MATE

Abstract

A charged particle array named MATE-PA, which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments (MATE), was constructed. The array comprised of 20 single-sided strip-silicon detectors covering approximately 10% of the solid angle. The detectors facilitated the detection of reaction-induced charged particles that penetrate the active volume of the MATE. The performance of MATE-PA has been experimentally studied using an alpha source and a 36-MeV \(^{14}\)N beam injected into the MATE chamber on the radioactive ion beam line in Lanzhou (RIBLL). The chamber was filled with a gas mixture of 95\(\%\) \(^4\)He and 5\(\%\) CO\(_2\) at a pressure of 500 mbar. The results indicated good separation of light-charged particles using the forward double-layer silicon detectors of MATE-PA. The energy resolution of the Si detectors was deduced to be approximately 1\(\%\) (\(\sigma\)) for an energy loss of approximately 10 MeV caused by the \(\alpha\) particles. The inclusion of MATE-PA improves particle identification and increases the dynamic range of the kinetic energy of charged particles, particularly that of the \(\alpha\) particles, up to approximately 15 MeV.