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Title: Ion kinetic dynamics in strongly-shocked plasmas relevant to ICF

Implosions of thin-shell capsules produce strongly-shocked (M > 10), low-density (ρ ~1 mg/cc -1), high-temperature (T i ~keV) plasmas, comparable to those produced in the strongly-shocked DT-vapor in inertial confinement fusion (ICF) experiments. A series of thin-glass targets filled with mixtures of deuterium and Helium-3 gas ranging from 7% to 100% deuterium was imploded to investigate the impact of multi-species ion kinetic mechanisms in ICF-relevant plasmas over a wide range of Knudsen numbers (N K ≡ λ ii/R). Anomalous trends in nuclear yields and burn-averaged ion temperatures in implosions with N K > 0.5, which have been interpreted as signatures of ion species separation and ion thermal decoupling, are found not to be consistent with single-species ion kinetic effects alone. Experimentally inferred Knudsen numbers predict an opposite yield trend to those observed, confirming the dominance of multi-species physics in these experiments. In contrast, implosions with N K ~ 0.01 follow the expected yield trend, suggesting single-species kinetic effects are dominant. In conclusion, the impact of the observed kinetic physics mechanisms on the formation of the hotspot in ICF experiments is discussed.
Authors:
 [1] ;  [1] ;  [2] ;  [3] ;  [3] ;  [3] ;  [3] ;  [3] ;  [3] ;  [4] ;  [4] ;  [4] ;  [4] ;  [1] ;  [2] ;  [2] ;  [2]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  2. Univ. of Rochester, Rochester, NY (United States)
  3. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
LLNL-CONF-703328
Journal ID: ISSN 0029-5515
Grant/Contract Number:
AC52-07NA27344
Type:
Accepted Manuscript
Journal Name:
Nuclear Fusion
Additional Journal Information:
Journal Volume: 57; Journal Issue: 6; Conference: 26th IAEA Fusion Energy Conference, Kyoto (Japan), 17-22 Oct 2016; Journal ID: ISSN 0029-5515
Publisher:
IOP Science
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 70 PLASMA PHYSICS AND FUSION; inertial confinement fusion; kinetic plasmas; multi-species plasmas; laser fusion experiments
OSTI Identifier:
1330748