Constraints on ion velocity distributions from fusion product spectroscopy

Nuclear Fushion

article

A.J. Crilly¹  B.D. Appelbe¹  O.M. Mannion²  W. Taitano³  E.P. Hartouni⁴  A.S. Moore⁴  M. Gatu-Johnson⁵  J.P. Chittenden¹ 

[1] Centre for Inertial Fusion Studies, The Blackett Laboratory, Imperial College;Sandia National Laboratories;Los Alamos National Laboratory;Lawrence Livermore National Laboratory;Massachusetts Institute of Technology, Plasma Science and Fusion Center

关键词: neutron spectroscopy;    inertial confinement fusion;    ion kinetics;    fusion productspectroscopy;    reaction kinematics;   

DOI  :  10.1088/1741-4326/ac90d5

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

Recent inertial confinement fusion experiments have shown primary fusion spectral moments which are incompatible with a Maxwellian velocity distribution description. These results show that an ion kinetic description of the reacting ions is necessary. We develop a theoretical classification of non-Maxwellian ion velocity distributions using the spectral moments. At the mesoscopic level, a monoenergetic decomposition of the velocity distribution reveals there are constraints on the space of spectral moments accessible by isotropic distributions. General expressions for the directionally dependent spectral moments of anisotropic distributions are derived. At the macroscopic level, a distribution of fluid element velocities modifies the spectral moments in a constrained manner. Experimental observations can be compared to these constraints to identify the character and isotropy of the underlying reactant ion velocity distribution and determine if the plasma is hydrodynamic or kinetic.

【 授权许可】

Unknown