Non-equilibrium between ions and electrons inside hot spots from National Ignition Facility experiments

Matter and Radiation at Extremes - Tập 2 - Trang 3-8 - 2017
Zhengfeng Fan1, Yuanyuan Liu1, Bin Liu1, Chengxin Yu1, Ke Lan1, Jie Liu1,2
1Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
2Center for Applied Physics and Technology, Peking University, Beijing 100871, China

Tóm tắt

The non-equilibrium between ions and electrons in the hot spot can relax the ignition conditions in inertial confinement fusion [Fan et al., Phys. Plasmas 23, 010703 (2016)], and obvious ion-electron non-equilibrium could be observed by our simulations of high-foot implosions when the ion-electron relaxation is enlarged by a factor of 2. On the other hand, in many shots of high-foot implosions on the National Ignition Facility, the observed X-ray enhancement factors due to ablator mixing into the hot spot are less than unity assuming electrons and ions have the same temperature [Meezan et al., Phys. Plasmas 22, 062703 (2015)], which is not self-consistent because it can lead to negative ablator mixing into the hot spot. Actually, this non-consistency implies ion-electron non-equilibrium within the hot spot. From our study, we can infer that ion-electron non-equilibrium exists in high-foot implosions and the ion temperature could be ∼9% larger than the equilibrium temperature in some NIF shots.

Tài liệu tham khảo

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