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Title: Hard X-ray Imaging for Measuring Laser Absorption Spatial Profiles on the National Ignition Facility

Conference ·
DOI:https://doi.org/10.1063/1.2216991· OSTI ID:897970

Hard x-ray (''Thin wall'') imaging will be employed on the National Ignition Facility (NIF) to spatially locate laser beam energy deposition regions on the hohlraum walls in indirect drive Inertial Confinement Fusion (ICF) experiments, relevant for ICF symmetry tuning. Based on time resolved imaging of the hard x-ray emission of the laser spots, this method will be used to infer hohlraum wall motion due to x-ray and laser ablation and any beam refraction caused by plasma density gradients. In optimizing this measurement, issues that have to be addressed are hard x-ray visibility during the entire ignition laser pulse with intensities ranging from 10{sup 13} to 10{sup 15} W/cm{sup 2}, as well as simultaneous visibility of the inner and the outer laser drive cones. In this work we will compare the hard x-ray emission calculated by LASNEX and analytical modeling with thin wall imaging data recorded previously on Omega and during the first hohlraum experiments on NIF. Based on these calculations and comparisons the thin wall imaging will be optimized for ICF/NIF experiments.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
897970
Report Number(s):
UCRL-CONF-221138; TRN: US200706%%161
Resource Relation:
Journal Volume: 77; Journal Issue: 10; Conference: Presented at: High Temperature Plasma Diagnostics, Williamsburg, VA, United States, May 07 - May 11, 2006
Country of Publication:
United States
Language:
English

References (6)

The upgrade to the OMEGA laser system journal January 1995
Radiation-Driven Hydrodynamics of High- Z Hohlraums on the National Ignition Facility journal November 2005
Development of the indirect‐drive approach to inertial confinement fusion and the target physics basis for ignition and gain journal November 1995
Use of thin wall imaging in the diagnosis of laser heated hohlraums journal January 1997
The National Ignition Facility: enabling fusion ignition for the 21st century journal November 2004
The flexible x‐ray imager journal February 1996