Development of GEM-TPC with gating grid for J-PARC hadron experiment

Sugimura, Hitoshi; Imai, Kenichi; Sako, Hiroyuki   ; Sato, Susumu  ; Ichikawa, Yudai   

We are now developing a new time projection chamber (TPC) surrounding a target to measure the emitted particles of short flight lengths under a high beam rate. The prototype of the TPC with GEM readout has been developed. The effective area is about 100mm 100mm 300mm (drift direction) and Beam particles go through the TPC perpendicular to the drift direction. A signal is amplified with three layers of GEM sheet and read out with anode pads of various sizes for the study of the TPC properties. The goal of particle rate at the TPC is over Hz. In order to operate under such high counting rate, we adopted a gating grid opened by an appropriate trigger. We have tested the TPC by using an electron beam at the Research Center for Electron Photon Science, Tohoku University. We report the results of the test experiment.