MeV Gamma-Ray Imaging Detector with micro-TPC

Toru Tanimori; Hidetoshi Kubo; Kentaro Miuchi; Tsutomu Nagayoshi; Reiko Orito; Atsushi Takada; Atsushi Takeda; Masaru Ueno

doi:10.1016/j.newar.2003.11.038

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MeV Gamma-Ray Imaging Detector with micro-TPC

Toru Tanimori·Hidetoshi Kubo·Kentaro Miuchi·Tsutomu Nagayoshi·Reiko Orito·Atsushi Takada·Atsushi Takeda·Masaru Ueno

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Abstract

We propose a new imaging gamma-ray detector in the MeV region. By measuring the directions and energies of not only a scattered gamma ray but also a recoil electron, the direction of an incident gamma ray would be essentially reconstructed event by event. Furthermore, one of two measured (zenith and azimuth) angles of a recoil electron gives us an additional redundancy which enables us to reject the background events by kinematic constraints. In order to measure the track of a recoil electron, the micro Time Projection Chamber($μ$-TPC) has been developed, which can measure the successive positions of the track of charged particles in a few hundred micron meter pitch. The $μ$-TPC consists of the new type of a gas proportional chamber: micro PIxel gas Chamber ($μ$-PIC) which is one of wireless gas chambers and expected to be robust and stable. Using this $μ$-TPC and the Anger camera for the detection of a scattered gamma ray, we have obtained the first gamma-ray image by the full reconstruction of the direction of gamma rays event by event.

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Toru Tanimori, Hidetoshi Kubo, Kentaro Miuchi, Tsutomu Nagayoshi, Reiko Orito, Atsushi Takada, Atsushi Takeda, Masaru Ueno. 2004-03-22. MeV Gamma-Ray Imaging Detector with micro-TPC. https://doi.org/10.1016/j.newar.2003.11.038

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