Dr Atsuhiko Ochi (Kobe University (JP))
The Micro Pixel Chamber (μ-PIC) using resistive electrodes have been developed and tested. The surface cathodes are made from resistive material, by which the electrical field is reduced when large current is flowed. Two-dimensional readouts are realized by oth anodes and pickup electrodes, on which signals are induced. High gas gain (>50000) was measured using 55Fe (5.9 keV) source, and very strong spark reduction was attained under fast neutron. The spark rate of resistive μ-PIC was only 1/10000 times less than that of normal μ-PIC in the gain of 10000. The planar MIP detector with no floating structure (such as wire, mesh or floating foil) is now realized by new μ-PIC with both high gain and good stability. In addition, using resistive cathodes, μ-PIC can be oprates by no HV applying on anodes. Neither AC coupling capacitors nor HV pull up resisters are needed for each anode electrode. Signal readout is drastically simplified by that configuration.