Study of primary knock-on atoms from high-energy proton bombardment

高能质子轰击初级碰撞原子的研究

• 批准号: 17K14918
• 负责人: 蔡 碧恩
• 金额: $ 2.83万
• 依托单位: Japan Atomic Energy Agency
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2017
• 资助国家: 日本
• 起止时间: 2017-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17K14918/
• 关键词: PKA; PHITS; Radiation Damage; gas ionization chamber; dE-E; particle identification; primary knock-on atoms; time of flight

Primary knock-on atoms (PKAs) play a fundamental role in radiation damage assessment for proton accelerators, and can also be used to validate physics models for simulating proton-induced nuclear reactions. This study was aim to develop a new measurement system, and by which to provide new experimental data of PKAs.PKAs created by high-energy proton bombardment consist of nuclides with a continuous mass range from 1 amu to the target nuclide mass, and with an energy spectrum from sub-MeV to several tens of MeV. The new measurement system we proposed in this study consists of two ultrafast timing detectors for time of flight (tof) measurement and a customized dE-E gas ionization chamber. The PKA isotopes are identified by combining the dE-E and tof-E relations, and then their energies can be determined by tof.The customized dE-E gas ionization chamber along with its gas flow system has been successfully built for this study. It was successfully tested at the Tandem Accelerator of Japan Atomic Energy Agency by using a calibration Am-241 alpha source. The detector performance was also confirmed with a 70-MeV proton beam bombarding a thin carbon target at CYRIC, Tohoku University, and the PKA elements were able to be identified for C, B, Be, and Li.The ultrafast timing detectors which include an ultrathin carbon foil, an electrostatic mirror, and a microchannel plate detector, were also built. However, the signals of the ultrafast timing detectors were noisy such that true events cannot be separated from background events, which has to be solved befor taking steps forward.

初级撞击原子（PKA）在质子加速器辐射损伤评估中起着重要作用，也可以用来验证模拟质子诱导核反应的物理模型。本研究的目的是建立一种新的测量系统，为PKA的实验研究提供新的数据。高能质子轰击产生的PKA由从1 amu到目标核素质量的连续质量范围的核素组成，其能谱从亚MeV到几十MeV。在这项研究中，我们提出的新的测量系统包括两个超快定时探测器的飞行时间（TOF）测量和定制的dE-E气体电离室。结合dE-E关系和tof-E关系识别PKA同位素，并利用tof确定其能量。为该研究定制了dE-E气体电离室沿着及其气流系统。在日本原子能机构的串列加速器上，利用校准的Am-241 α源成功地进行了测试。在东北大学的CYRIC实验室，用70 MeV质子束轰击薄碳靶，确认了PKA元素的C、B、Be、Li等。此外，还制作了由碳箔、静电镜、微通道板等构成的超快定时探测器。然而，超快定时探测器的信号是有噪声的，使得真实事件不能与背景事件分离，这必须在采取步骤之前解决。

项目成果

Establishment of a New Detection system for Measuring Primary Knock-on Atoms and Fission Fragments

建立测量初级碰撞原子和裂变碎片的新检测系统

• 发表时间: 2017
• 作者: H. NOGE;W.J. YAHYA;Y. UENO;Pi-En Tsai
• 通讯作者: Pi-En Tsai

Development of a gas ionization chamber for PKA charge distribution measurements

开发用于 PKA 电荷分布测量的气体电离室

• 发表时间: 2019
• 作者: Liang Yunye;Khazaei Mohammad;Ranjbar Ahmad;Arai Masao;Yunoki Seiji;Kawazoe Yoshiyuki;Weng Hongming;Fang Zhong;Mohammad Khazaei;Pi-En Tsai
• 通讯作者: Pi-En Tsai

Development of a New Measurement System for Primary Knock-on Atoms (PKA)

开发初级碰撞原子 (PKA) 的新型测量系统

• 发表时间: 2018
• 期刊: CYRIC Annual Report 2016-2017
• 作者: Tsai P.E.,;Iwamoto Y.;Hagiwara M.;Sato T.;Satoh D.;Abe S.;Itoh M.;and Watabe H
• 通讯作者: and Watabe H

Establishment of a Novel Detection System for Measuring Primary Knock-on Atoms

建立测量初级碰撞原子的新型检测系统

• 发表时间: 2017
• 作者: Liang Yunye;Khazaei Mohammad;Ranjbar Ahmad;Arai Masao;Yunoki Seiji;Kawazoe Yoshiyuki;Weng Hongming;Fang Zhong;Mohammad Khazaei;Pi-En Tsai;Pi-En Tsai
• 通讯作者: Pi-En Tsai

5.Development of the Detection System for 70-MeV Proton-induced PKAs

5.70MeV质子诱导PKA检测系统的研制

• 发表时间: 2018
• 作者: 加藤岳仁;他;Pi-En Tsai
• 通讯作者: Pi-En Tsai