Details

Autor(en) / Beteiligte

• Scott, R. H. H.
• Glize, K.
• Antonelli, L.
• Khan, M.
• Theobald, W.
• Wei, M.
• Betti, R.
• Stoeckl, C.
• Seaton, A. G.
• Arber, T. D.
• Barlow, D.
• Goffrey, T.
• Bennett, K.
• Garbett, W.
• Atzeni, S.
• Casner, A.
• Batani, D.
• Li, C.
• Woolsey, N.

Titel

Shock Ignition Laser-Plasma Interactions in Ignition-Scale Plasmas

Ist Teil von

• Physical review letters, 2021-08, Vol.127 (6), p.065001-065001, Article 065001

Ort / Verlag

College Park: American Physical Society

Erscheinungsjahr

2021

Link zum Volltext

Quelle

American Physical Society

Beschreibungen/Notizen

• We use a subignition scale laser, the 30 kJ Omega, and a novel shallow-cone target to study laser-plasma interactions at the ablation-plasma density scale lengths and laser intensities anticipated for direct drive shock-ignition implosions at National Ignition Facility scale. Our results show that, under these conditions, the dominant instability is convective stimulated Raman scatter with experimental evidence of two plasmon decay (TPD) only when the density scale length is reduced. Particle-in-cell simulations indicate this is due to TPD being shifted to lower densities, removing the experimental back-scatter signature and reducing the hot-electron temperature. The experimental laser energy-coupling to hot electrons was found to be 1%–2.5%, with electron temperatures between 35 and 45 keV. Radiation-hydrodynamics simulations employing these hot-electron characteristics indicate that they should not preheat the fuel in MJ-scale shock ignition experiments.