We report a new scenario of time-of-flight (TOF) technique in which fast neutrons and delayed gamma-ray signals were both recorded in a millisecond time window in harsh environments induced by high-intensity lasers. The delayed gamma signals, arriving far later than the original fast neutron and often being ignored previously, were identified to be the results of radiative captures of thermalized neutrons. The linear correlation between gamma photon number and the fast neutron yield shows that these delayed gamma events can be employed for neutron diagnosis. This method can reduce the detecting efficiency dropping problem caused by prompt high-flux gamma radiation, and provides a new way for neutron diagnosing in high-intensity laser-target interaction experiments.
@article{arxiv.1709.06561,
title = {Demonstration of Laser-produced Neutron Diagnostic by Radiative Capture Gamma-rays},
author = {Xiaopeng Zhang and Wenqing Wei and Changbo Fu and Xiaohui Yuan and Songhai An and Yanqing Deng and Yuan Fang and Jian Gao and Xulei Ge and Bing Guo and Chuangye He and Peng Hu and Neng Hua and Weiman Jiang and Liang Li and Mengting Li and Yifei Li and Yutong Li and Guoqiang Liao and Feng Liu and Longxiang Liu and Hongwei Wang and Pengqian Yang and Su Yang and Tao Yang and Guoqiang Zhang and Yue Zhang and Baoqiang Zhu and Xiaofeng Xi and Jianqiang Zhu and Zhengming Sheng and Jie Zhang},
journal= {arXiv preprint arXiv:1709.06561},
year = {2018}
}