Application of capillary plate to a new type of imaging radiation detector

Using a new device of a capillary plate, a new type of gas proportional counter was constructed. The capillary plate gas proportional counter (CGPC) was found to operate stably up to high gas gain. The energy resolution was as well as a typical proportional counter. Moreover, the CGPC has timing resolution of several μ sec by using the charged signals from the anode in the capillary plate. We constructed an optical imaging apparatus with a CCD camera. Combining the CGPC with the optical imaging apparatus, we investigated the performance of the new type of imaging radiation detector using α particles. As the results, we obtained the first evidence that the scintillation emission due to the gas multiplication occurs in each capillary. Also, the track of an α particle was clearly observed by setting up carefully the reduced field of the drift region. Now, we are trying to detect a track of a electron ejected by photoelectric absorption of X ray. By employing the new type of imaging radiation detector, we are planning to develop an X-ray polarimeter with high imaging power, good timing resolution, and moderate energy resolution simultaneously. We expect the new type of imaging radiation detector can apply to a lot of fields utilizing the radiation. In near future, we will present the new results. (author)