Update on ignition studies at CEA

Abstract.This article sums up the theoretical and experimental studies about ignition. Three experiments are salient this year on the Omega laser in collaboration with DOE laboratories (1) 3 cones of beams allow to mimic the LMJ configuration and to get symmetry measurements. (2) We measured perturbations due to hydro-instability in CHGe planar samples with face-on and side-on radiographs. (3) We improved our nuclear diagnostics, particularly the neutron image system tested on direct drive implosions. As far as LMJ target design is concerned, we defined a preliminary domain corresponding to the possible operation at 2ω. At 3ω we studied the low mode instability effects on the DT deformation (due to the laser or to the target) and on the yield. The stability is clearly improved with graded doped CH for our nominal capsule L1215.

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