Development of a time projection chamber using gas electron multipliers (GEM-TPC)

A prototype of time projection chambers using gas electron multipliers (GEM-TPC) has been developed for relativistic heavy ion collision experiments. The performance of the GEM-TPC was investigated using particle beams at KEK with 3 kinds of gases (Ar(90%)-CH/sub 4/(10%), Ar(70%)-C/sub 2/H/sub 6/(30%) and CF/sub 4/). Detection efficiency of 99%, spatial resolution of 80 /spl mu/m in the pad-row direction and double track resolution of 12 mm in the drift direction were achieved. The test results show that the GEM-TPC meets requirements of relativistic heavy ion collision experiments. This paper describes the configuration and performance of the GEM-TPC.