Diagnostic approach of using an electron tracking compton gamma-ray camera based on small animal and phantom experiments

A conventional Compton camera reconstructs initial gamma-rays direction as circle. A Compton gamma-ray camera which we have developed can detect electron tracks. So our camera can reconstruct the initial gamma-rays as arc. It makes getting the low noise of image. In this paper, we report the results of three version of electron tracking camera. One is 10 x 10 x 10 cm³ Time Projection Chamber (TPC) as a scatter detector and 15 x 15 cm² GSO pixel scintillator array (PSA) as an absorber. Second is a 10 x 10 x 10 cm³ TPC and a 10 x 10 cm2 LaBr₃ PSA. The energy resolution of LaBr₃ scintillator is about 2 times better than GSO scintillator. Third is a 30 x 30 x 15 cm³ TPC and a 30 x 30 cm² GSO pixel PSA. The efficiency of this system is better than 10 cm³ cube Compton gammra-ray camera.