2002 Fiscal Year Final Research Report Summary
Development of wide view gamma-ray Imaging Detector
| Project/Area Number |
12354002
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
素粒子・核・宇宙線
|
|---|
| Research Institution | KYOTO UNIVERSITY |
|---|
Principal Investigator |
TANIMORI Toru Kyoto University Dept. of Physics Professor, 大学院・理学研究科, 教授 (10179856)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KUBO Hidetoshi Kyoto University Dept. Research Associate, 大学院・理学研究科, 助手 (40300868)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Keywords | MeV gamma-rays / gamma-rays Imaging / Compton Scattering / MSGC / Gas Detector / Anguar Camera / TPC |
|---|
| Research Abstract |
We have proposed the new imaging method of MeV gamma rays. By measuring the direction and energy of not only a scattered gamma ray but also a scattered electron, the direction of an incident gamma ray would be principally reconstructed event by event, and a full imaging would be realized. Furthermore, one of two measured (zenith and azimuthal) angles of a scattered electron gives co an additional redundancy which enable us to reject almost all the background events by kinematic fitting. In order to detect such a fine track of the recoil electron, a fine imaging gas detector made by the micro printed board technology was proposed here.
In order to obtain 3-D track of a scattered electron, the micro Time Projection Chamber(TPC) has been developed, which measures the position of the track in a few hundred micron meter pitch successively. This TPC consists of the new type of a gas proportional chamber : Micro Pixel Gas Chamber (MPGC) which is a one of wireless gas chamber and expected to be more robust and reliable than Micro Strip Gas Chamber. Here 10cm×10cm 2D-MPGC with a 400 μm pitch pixel was developed, and the high gain of 〜 15000 and the stable operation as a micro TPC with a moderated gain of 〜 5000 during one month have been achieved. Also a compact Anguar camera consisting of a 10cm×10cm×2.5cm NaI scintillator and a 5×5 one-inch phototube array was constructed to detect a recoil gamma ray. Using the micro TPC and the Anguar camera, we successfully obtained the first gamma-ray image by the full reconstruction of the direction of gamma rays event by event. Although obtained angular resolution of 〜 30°is not so good due to the inefficiency of the MPGC, it is the first time in the world to demonstrate the possibility of full gamma ray imaging.
|
