Evidence for a Bubble-Competition Regime in Indirectly Driven Ablative Rayleigh-Taylor Instability Experiments on the NIF
In this paper, we investigate on the National Ignition Facility the ablative Rayleigh-Taylor instability in the transition from weakly nonlinear to highly nonlinear regimes. A planar plastic package with preimposed two-dimensional broadband modulations is accelerated for up to 12 ns by the x-ray drive of a gas-filled Au radiation cavity with a radiative temperature plateau at 175 eV. This extended tailored drive allows a distance traveled in excess of 1 mm for a 130 μm thick foil. Measurements of the modulation optical density performed by x-ray radiography show that a bubble-merger regime for the Rayleigh-Taylor instability at an ablation front is achieved for the first time in indirect drive. Finally, the mutimode modulation amplitudes are in the nonlinear regime, grow beyond the Haan multimode saturation level, evolve toward the longer wavelengths, and show insensitivity to the initial conditions.
- Authors:
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[1]
; [1]
; [1]
; [2]
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- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Alternative Energies and Atomic Energy Commission (CEA), Arpajon (France)
- Publication Date:
- Report Number(s):
- LLNL-JRNL-670326
Journal ID: ISSN 0031-9007
- Grant/Contract Number:
- AC52-07NA27344
- Type:
- Accepted Manuscript
- Journal Name:
- Physical Review Letters
- Additional Journal Information:
- Journal Volume: 114; Journal Issue: 21; Journal ID: ISSN 0031-9007
- Publisher:
- American Physical Society (APS)
- Research Org:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Org:
- USDOE
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
- OSTI Identifier:
- 1376014
- Alternate Identifier(s):
- OSTI ID: 1193895
- Free Publicly Accessible Full Text
- Accepted Manuscript (Publisher)
-
Accepted Manuscript (DOE)
- Publisher's Version of Record
- https://doi.org/10.1103/PhysRevLett.114.215004