skip to main content

SciTech ConnectSciTech Connect

Title: Validating hydrodynamic growth in National Ignition Facility implosions

We present new hydrodynamic growth experiments at the National Ignition Facility, which extend previous measurements up to Legendre mode 160 and convergence ratio 4, continuing the growth factor dispersion curve comparison of the low foot and high foot pulses reported by Casey et al. [Phys. Rev. E 90, 011102(R) (2014)]. We show that the high foot pulse has lower growth factor and lower growth rate than the low foot pulse. Using novel on-capsule fiducial markers, we observe that mode 160 inverts sign (changes phase) for the high foot pulse, evidence of amplitude oscillations during the Richtmyer-Meshkov phase of a spherically convergent system. Post-shot simulations are consistent with the experimental measurements for all but the shortest wavelength perturbations, reinforcing the validity of radiation hydrodynamic simulations of ablation front growth in inertial confinement fusion capsules.
Authors:
; ; ; ; ;  [1]
  1. Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
Publication Date:
OSTI Identifier:
22410405
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABLATION; CAPSULES; CONVERGENCE; DISTURBANCES; FIDUCIAL MARKERS; GROWTH FACTORS; HYDRODYNAMICS; IMPLOSIONS; INERTIAL CONFINEMENT; LEGENDRE POLYNOMIALS; OSCILLATIONS; PERTURBATION THEORY; PULSES; SIMULATION; SPHERICAL CONFIGURATION; US NATIONAL IGNITION FACILITY; WAVELENGTHS