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arXiv · 1406.7108

Species separation and modification of neutron diagnostics in inertial-confinement fusion

Aurelie Inglebert·Benoit Canaud·Olivier Larroche
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Abstract

The different behaviours of deuterium (D) and tritium (T) in the hot spot of marginally-igniting cryogenic DT inertial-confinement fusion (ICF) targets are investigated with an ion Fokker-Planck model. With respect to an equivalent single-species model, a higher density and a higher temperature are found for T in the stagnation phase of the target implosion. In addition, the stagnating hot spot is found to be less dense but hotter than in the single-species case. As a result, the fusion reaction yield in the hot spot is significantly increased. Fusion neutron diagnostics of the implosion find a larger ion temperature as deduced from DT reactions than from DD reactions, in good agreement with NIF experimental results. ICF target designs should thus definitely take ion-kinetic effects into account.

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Aurelie Inglebert, Benoit Canaud, Olivier Larroche. 2014-06-27. Species separation and modification of neutron diagnostics in inertial-confinement fusion. https://doi.org/10.1209/0295-5075%2F107%2F65003

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