Gamma-alpha ray coincidence detection from micro proton beam for fluorine distribution measurement

• Project/Area Number: 22540311
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Osaka University
• Principal Investigator: SUGAYA Yorihito 大阪大学, 核物理研究センター, 助教 (80324747)
• Project Period (FY): 2010 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2012: ¥390,000 (Direct Cost: ¥300,000、Indirect Cost: ¥90,000); Fiscal Year 2011: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2010: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
• Keywords: 原子核(実験) / マイクロ陽子ビーム / 歯質中のフッ素濃度 / 原子核（実験）

Research Abstract

In the dental field, it is epidemiologically known that fluorine is useful for preventingthe progression of dental caries. We had developed the fluorine distribution measurement in tooth by detecting gamma rays from an in-air micro proton beam at the Wakasa Wan Energy Research Center. In this time, we developed a coincidence measurement between gamma rays and alpha rays in order to limit the depth of a fluorine distribution in the beam direction. An alpha ray yield has been obtained as 0.4 % of the gamma ray yield for 3.4-MeV proton beam. It is found that to measure the fluorine distribution in tooth, the larger alpha ray yield is required.