A miniature prototype of Time Projection Chambers for CSR External-Target Experiment

A miniature prototype of time projection chamber for the cooling storage ring external-target experiment (CEE) at the Heavy Ion Research Facility in Lanzhou (HIRFL) was designed for three-dimensional tracking of charged particles produced in heavy-ion collisions at the target region and for particle identification. The prototype consists of a TPC detector chamber with active volume of 9 cm (height), 10 cm (length) and 10 cm (width), gas electron multiplier (GEM) detector readout and SAMPA-based electronics. This work describes design, track reconstruction method and performance of the prototype. The energy resolution is 11.03% sigma using a 55Fe x-ray source. Using heavy-ion beam of 150 MeV/u Fe, the test results show that the two-dimensional position resolution and drift time resolution of the prototype are better than 400 μm and 20 ns, respectively.