Speaker
Dr
Tetsuya Mizumoto
(Kyoto University)
Description
We have developed a Compton camera that can determine the arrival directions of sub-MeV/MeV gamma rays for gamma-ray astronomy observations. This is a hybrid detector consisting of a gaseous TPC, which has a two-dimensional position sensitive gaseous detector with pixel anode electrodes at a pitch of 400 micrometers, and a position-sensitive scintillation camera enclosing the TPC. Some incident MeV gamma rays produce recoil electrons within the TPC whose tracks can be measured in three dimensions. Additionally, scattered gamma rays are absorbed in the scintillation camera where we measure their absorption points and energies. From these data, we can reconstruct the arrival direction of every incident MeV photon to about 1 degree from the kinematical analysis, so we can reject a large fraction of background events. This detector has a large field of view (about 3str). In 2006, in the first measurement of SMILE (Sub-MeV gamma ray Imaging Loaded-on-balloon Experiment), we observed diffuse cosmic and atmospheric gamma rays at balloon altitudes with a 10-cubic-centimeter Compton camera as the first step toward a future all sky survey with high sensitivity. As the next step, we are planning to test the gamma ray imaging performance of a 30-cubic-centimeter Compton camera, which has a larger effective area and higher angular resolution than the Compton camera used for SMILE-I, by observing the Crab Nebula from balloon altitudes starting from 2012 (SMILE-II). For the SMILE-II balloon measurement, a reduction in size and energy consumption of the electronics along with a performance survey of the experimental devices and experimental simulations are necessary. In this conference, we will present an overview of the Compton camera and the status of SMILE-II.
Preferred medium (Oral/poster)
Oral
Author
Dr
Tetsuya Mizumoto
(Kyoto University)
Co-authors
Dr
Atsushi Takada
(Kyoto University)
Dr
Hidetoshi Kubo
(Kyoto University)
Dr
Joseph Parker
(Kyoto University)
Dr
Kazuki Ueno
(RIKEN)
Dr
Kentaro Miuchi
(Kyoto University)
Mr
Kiseki Nakamura
(Kyoto University)
Mr
Satoru Iwaki
(Kyoto University)
Dr
Shigeto Kabuki
(Tokai University)
Mr
Shotaro Komura
(Kyoto University)
Dr
Shunsuke Kurosawa
(Tohoku University)
Mr
Tatsuya Sawano
(Kyoto University)
Prof.
Toru Tanimori
(Kyoto University)
Mr
Yasushi Sato
(Kyoto University)
Mr
Yoshihiro Matsuoka
(Kyoto University)
Dr
Yuji Kishimoto
(High Energy Accelerator Research Organization)
