Performance of the TPC with micro pixel chamber readout: micro-TPC

Micro-TPC, a time projection chamber (TPC) with micro pixel chamber (/spl mu/-PIC) readout was developed for the detection of the three dimensional fine (/spl sim/sub-millimeter) tracks of charged particles. We have developed a two-dimensional position sensitive gaseous detector, or the /spl mu/-PIC, with the detection area of 10 /spl times/ 10 cm/sup 2/ and 65536 anode electrodes of 400 /spl mu/m pitch. We achieved the gas gain of over /spl times/10/sup 4/ without any other multipliers. With the pipe-line readout system developed for the /spl mu/-PIC, we detected high intersity X-rays at the rate as high as 7.7Mcps. The TPC has the drift length of 8 cm and the uniform electric field of 0.4 kV/cm. We tested the performance of the micro-TPC and we took the three-dimensional tracks of the electrons. We also developed a prototype of the MeV Gamma-ray imaging detector which is a hybrid of the micro-TPC with NaI(Tl) scintillators and we have confirmed its concept by showing the reconstructed gamma-ray event.