中国物理B ›› 1999, Vol. 8 ›› Issue (10): 768-775.doi: 10.1088/1004-423X/8/10/006

• • 上一篇    下一篇

NEUTRON DETECTOR FOR FUSION BURN HISTORY MEASUREMENTS

吴时彬1, 伍凡1, 杨建伦2, 王根兴2, 朱启华2, 温树槐2, 刘忠礼2, 杨洪琼2, 唐正元2   

  1. (1)Institute of Photoelectric Technology, Chinese Academy of Sciences, Chengdu 610209, China; (2)Southwest Institute of Nuclear Physics and Chemistry, P. O. Box 525-73, Chengdu 610003, China
  • 收稿日期:1999-05-04 出版日期:1999-12-25 发布日期:2005-08-06
  • 基金资助:
    Project supported by the National High Technology Inertial Confinement Fusion Foundation of China (Grant No. 863-416-3-4.8) and the Science foundation of China Academy of Engineering Physics (Grant No. 990215).

NEUTRON DETECTOR FOR FUSION BURN HISTORY MEASUREMENTS

Yang Jian-lun (杨建伦)a, Wang Gen-xing (王根兴)a, Zhu Qi-hua (朱启华)a, Wen Shu-huai (温树槐)a, Liu Zhong-li (刘忠礼)a, Yang Hong-qiong (杨洪琼)a, Tang Zheng-yuan (唐正元)a, Wu Shi-bin (吴时彬)b, Wu Fan (伍凡)b   

  1. a Southwest Institute of Nuclear Physics and Chemistry, P. O. Box 525-73, Chengdu 610003, China; b Institute of Photoelectric Technology, Chinese Academy of Sciences, Chengdu 610209, China
  • Received:1999-05-04 Online:1999-12-25 Published:2005-08-06
  • Supported by:
    Project supported by the National High Technology Inertial Confinement Fusion Foundation of China (Grant No. 863-416-3-4.8) and the Science foundation of China Academy of Engineering Physics (Grant No. 990215).

摘要: We have designed a fast, sensitive neutron detector for recording the fusion history of inertial confinement fusion experiments. With a response time of <40 ps, it was for burn history measurements for deuterium/tritium-filled targets producing as few as ~108 neutrons/shot. The detector is based on the fast rise-time (<20 ps) of BC422 plastic scintillator which, shaped in thin cylinder sheet or curved (in a geometry compensating way) plate, acts as a neutron-to-light converter in a Pb shielding. The Pb shielding shields the scintillator from target X-ray, scattered light and target debris and allows the scintillator to be positioned within 3 cm from the target. The scintillator emits light with wavelengths from 350 to 450 nm. A group of achromatic lens relays the scintillator image along a 1 m optical path to the S20 photocathode of a streak camera outside the chamber. Lens coupling was chosen to give acceptable temporal dispersion. In the design phase, a computer code was programmed to calculate and improve the physical parameters of the optical system, such as light collection efficiency, time dispersion, image position, intensity distribution on the image plane, etc. Some of these parameters were finally measured using a deuterium lamp and a piece of BC422 scintillator activated by X-ray or 0.35 μm laser pulse. The measured results agree well with the prediction of the computer code.

Abstract: We have designed a fast, sensitive neutron detector for recording the fusion history of inertial confinement fusion experiments. With a response time of <40 ps, it was for burn history measurements for deuterium/tritium-filled targets producing as few as ~108 neutrons/shot. The detector is based on the fast rise-time (<20 ps) of BC422 plastic scintillator which, shaped in thin cylinder sheet or curved (in a geometry compensating way) plate, acts as a neutron-to-light converter in a Pb shielding. The Pb shielding shields the scintillator from target X-ray, scattered light and target debris and allows the scintillator to be positioned within 3 cm from the target. The scintillator emits light with wavelengths from 350 to 450 nm. A group of achromatic lens relays the scintillator image along a 1 m optical path to the S20 photocathode of a streak camera outside the chamber. Lens coupling was chosen to give acceptable temporal dispersion. In the design phase, a computer code was programmed to calculate and improve the physical parameters of the optical system, such as light collection efficiency, time dispersion, image position, intensity distribution on the image plane, etc. Some of these parameters were finally measured using a deuterium lamp and a piece of BC422 scintillator activated by X-ray or 0.35 μm laser pulse. The measured results agree well with the prediction of the computer code.

中图分类号:  (Scintillation detectors)

  • 29.40.Mc
85.60.Ha (Photomultipliers; phototubes and photocathodes) 25.45.Hi (Transfer reactions) 25.60.Pj (Fusion reactions) 52.58.-c (Other confinement methods)