Measurements of an Ablator-Gas Atomic Mix in Indirectly Driven Implosions at the National Ignition Facility

We present the first results from an experimental campaign to measure the atomic ablator-gas mix in the deceleration phase of gas-filled capsule implosions on the National Ignition Facility. Plastic capsules containing CD layers were filled with tritium gas; as the reactants are initially separated,...

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Bibliographic Details
Main Authors: Frenje, Johan A., Gatu Johnson, Maria, Petrasso, Richard D.
Other Authors: Massachusetts Institute of Technology. Plasma Science and Fusion Center
Format: Article
Language:en_US
Published: American Physical Society 2014
Online Access:http://hdl.handle.net/1721.1/85083
https://orcid.org/0000-0002-1020-3501
Description
Summary:We present the first results from an experimental campaign to measure the atomic ablator-gas mix in the deceleration phase of gas-filled capsule implosions on the National Ignition Facility. Plastic capsules containing CD layers were filled with tritium gas; as the reactants are initially separated, DT fusion yield provides a direct measure of the atomic mix of ablator into the hot spot gas. Capsules were imploded with x rays generated in hohlraums with peak radiation temperatures of ~294  eV. While the TT fusion reaction probes conditions in the central part (core) of the implosion hot spot, the DT reaction probes a mixed region on the outer part of the hot spot near the ablator–hot-spot interface. Experimental data were used to develop and validate the atomic-mix model used in two-dimensional simulations.