| Project/Area Number |
10305009
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| Research Category |
Grant-in-Aid for Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Applied physics, general
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| Research Institution | Waseda University |
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Principal Investigator |
KIKUCHI Jun Waseda Univ., Advanced Research Institute, Professor, 理工学総合研究センター, 教授 (50063665)
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| Co-Investigator(Kenkyū-buntansha) |
YAMAMOTO Mikio National Institute of Radiological Sciences, Research Center for Charged Particle Therapy, Head of Special Research of Bio-Emission Laboratory, 室長 (80166826)
SUZUKI Satosi Waseda Univ., Advanced Research Institute, Associate Professor, 理工学総合研究センター, 助教授 (30318828)
DOKE Tadayoshi Waseda Univ., Honorary Professor, 理工学総合研究センター, 名誉教授 (60063369)
OKADA Hiroyuki Waseda Univ., Advanced Research Institute, Assistant Professor, 理工学総合研究センター, 講師 (20308258)
MORI Toshinori The University of Tokyo, International Center for Elementary Particle Physics Associate Professor, 素粒子物理国際研究センター, 助教授 (90220011)
高島 健 名古屋大学, 理学部, 助手 (10298193)
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| Project Period (FY) |
1998 – 2000
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥35,400,000 (Direct Cost: ¥35,400,000)
Fiscal Year 2000: ¥5,800,000 (Direct Cost: ¥5,800,000)
Fiscal Year 1999: ¥13,100,000 (Direct Cost: ¥13,100,000)
Fiscal Year 1998: ¥16,500,000 (Direct Cost: ¥16,500,000)
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| Keywords | Liquid Xe radiation detector / PET / Liquid noble gas radiation detector / Gamma ray detector / PMT for low temperature / Purification of noble gas / Scintillation of liquid noble gas |
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| Research Abstract |
Liquid Xe is transparent liquid with atomic number 54 and density about 3.0 g/cm^3. For gamma rays its scintillation efficiency is almost same as NaI(T1) and the decay time constants of scintillation, 2nsec and 22nsec, are much faster than that of NaI(T1). It is estimated that the high energy resolution will be obtained, by detecting direct light with a plural PMTs, without using the reflected light. Also it is possible to estimate the reaction position of the gamma ray by comparing the output from plural PMTs. By the simulation for the 0.5 MeV gamma ray, the position resolution of several mm was obtained with the good condition. Thereupon, we think the possibility of new-type PET using liquid Xe as detector medium and produced the liquid Xe detector and made to obtain the experimental data needed for PET development. The chamber is the cylinder forms of 2 layers and the outside layer is evacuated vacuously for heat insulation and detector part of PMTs is included in the inside layer. The inside layer is filled with liquid xenon and the detector part of 44 PMTs is set in it. The windows are the honey cam window made of the stainless steel of 500 μm thick at inside and the miler window of 100 μm thick at outside. The effective volume is 12X12X12 cm^3 that is surrounded with 44 PMTs of 1 inch and 2 inch. PMTs that we developed this time are 2 inch cylinder type(R6041-06MOD) and 1 inch rectangular type (R5900-06MOD) made by Hamamatsu Photonics company, and these hold the quartz window to have high transmission efficiency for vacuum ultraviolet light and is designed to act without any problem even with the low temperature (-110 ℃) and the high pressure (3atm). Also, it is made to decrease the outgas or the impurities that becomes the cause of the decrease of scintillation light. The position resolution is 7.8 mm and the time resolution is 0.69nsec. In the central part of effective volume, the energy resolution is 45 % for 511 keV gamma ray.
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