Ultrashort Time-Integrated Diagnosis of Laser-Heated Deuterium Ions in Dense Plasma via Fusion Neutron Spectra

Jie Feng; Hao Xu; Mingxuan Wei; Mingyang Zhu; Xichen Hu; Bingzhan Shi; Fuyuan Wu; Weijun Zhou; Wenchao Yan; Guoqiang Zhang; Jinguang Wang; Yifei Li; Xin Lu; Liming Chen

arXiv · 2509.00659

Ultrashort Time-Integrated Diagnosis of Laser-Heated Deuterium Ions in Dense Plasma via Fusion Neutron Spectra

Jie Feng·Hao Xu·Mingxuan Wei·Mingyang Zhu·Xichen Hu·Bingzhan Shi·Fuyuan Wu·Weijun Zhou·Wenchao Yan·Guoqiang Zhang·Jinguang Wang·Yifei Li·Xin Lu·Liming Chen

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Abstract

The ultrashort time-integrated diagnosis of ions plays a vital role in high energy density physics research. However, it is extremely challenging to measure in experiment. Here, we demonstrate a reliable approach for investigating the dynamics of deuterium ions in dense plasma. By irradiating a heavy water stream with the hundred Hertz repetitive intense femtosecond laser pulses, the neutrons from D(D,n)3He reaction can be detected via a single Time-of-Flight detector to accumulate the spectrum with a fine energy-resolution. This spectrum has been utilized to calculate the temperature and angular distribution of deuterium ions transported in plasma. And the calculated results are well verified by particle-in-cell simulations of deuterium ions dynamics. Our method paves a new way for diagnosing ions picoseconds time-integrated dynamics in plasma and holds great potential for understanding the ions transport process in high-energy density matters and studying laser plasma ion acceleration.

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Jie Feng, Hao Xu, Mingxuan Wei, Mingyang Zhu, Xichen Hu, Bingzhan Shi, Fuyuan Wu, Weijun Zhou, Wenchao Yan, Guoqiang Zhang, Jinguang Wang, Yifei Li, Xin Lu, Liming Chen. 2025-08-31. Ultrashort Time-Integrated Diagnosis of Laser-Heated Deuterium Ions in Dense Plasma via Fusion Neutron Spectra. https://arxiv.org/abs/2509.00659

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