Observed transition from Richtmyer-Meshkov jet formation through feedout oscillations to Rayleigh-Taylor instability in a laser target

Y. Aglitskiy; M. Karasik; A. L. Velikovich; V. Serlin; J. Weaver; T. J. Kessler; S. P. Nikitin; A. J. Schmitt; S. P. Obenschain; N. Metzler; J. Oh

doi:10.1063/1.4764287

arXiv · 1207.6973

Observed transition from Richtmyer-Meshkov jet formation through feedout oscillations to Rayleigh-Taylor instability in a laser target

Y. Aglitskiy·M. Karasik·A. L. Velikovich·V. Serlin·J. Weaver·T. J. Kessler·S. P. Nikitin·A. J. Schmitt·S. P. Obenschain·N. Metzler·J. Oh

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Abstract

Experimental study of hydrodynamic perturbation evolution triggered by a laser-driven shock wave breakout at the free rippled rear surface of a plastic target is reported. At sub-megabar shock pressure, planar jets manifesting the development of the Richtmyer-Meshkov-type instability in a non-accelerated target are observed. As the shock pressure exceeds 1 Mbar, an oscillatory rippled expansion wave is observed, followed by the "feedout" of the rear-surface perturbations to the ablation front and the development of the Rayleigh-Taylor instability, which breaks up the accelerated target.

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Y. Aglitskiy, M. Karasik, A. L. Velikovich, V. Serlin, J. Weaver, T. J. Kessler, S. P. Nikitin, A. J. Schmitt, S. P. Obenschain, N. Metzler, J. Oh. 2012-07-30. Observed transition from Richtmyer-Meshkov jet formation through feedout oscillations to Rayleigh-Taylor instability in a laser target. https://doi.org/10.1063/1.4764287

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