skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Indirect-drive radiation uniformity in tetrahedral hohlraums

Abstract

Tetrahedral hohlraums, by which are understood spherical hohlraums with four laser entrance holes (LEH{close_quote}s) placed at or near the vertices of a tetrahedron, are proposed for the National Ignition Facility (NIF) [J. Lindl, Phys. Plasmas {bold 2}, 3933 (1995)] and the upgraded OMEGA laser [T. R. Boehly {ital et} {ital al}., Rev. Sci. Instrum. {bold 66}, 508 (1995)]. All but four of the 48 NIF beams can irradiate a tetrahedral hohlraum, assuming that 72 beam ports are provided to accommodate direct drive. On OMEGA, the target chamber provides an exact tetrahedral symmetry, permitting the irradiation of tetrahedral hohlraums with all 60 beams. Hohlraum designs are optimized using a new three-dimensional view-factor program called Buttercup, which traces all beam paths through the hohlraum and calculates the radiation flux on the capsule for different values of the albedo. Good irradiation uniformity ({approximately}2{percent} rms) can be obtained on the capsule at all times during the implosion, even with identical beam temporal histories, in contrast to the case of cylindrical hohlraums where {open_quote}{open_quote}beam phasing{close_quote}{close_quote} is needed. {copyright} {ital 1996 American Institute of Physics.}

Authors:
;  [1]
  1. Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)
Publication Date:
Research Org.:
Univ. of Rochester, NY (United States)
OSTI Identifier:
383795
DOE Contract Number:  
FC03-92SF19460
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 3; Journal Issue: 10; Other Information: PBD: Oct 1996
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; LASER-PRODUCED PLASMA; INDIRECT DRIVE LASER IMPLOSION; LASER-RADIATION HEATING; ICF DEVICES; HOT PLASMA; X RADIATION; DESIGN; OMEGA FACILITY; LASER FUSION REACTORS; TETRAHEDRAL CONFIGURATION

Citation Formats

Schnittman, J D, and Craxton, R S. Indirect-drive radiation uniformity in tetrahedral hohlraums. United States: N. p., 1996. Web. doi:10.1063/1.871511.
Schnittman, J D, & Craxton, R S. Indirect-drive radiation uniformity in tetrahedral hohlraums. United States. doi:10.1063/1.871511.
Schnittman, J D, and Craxton, R S. Tue . "Indirect-drive radiation uniformity in tetrahedral hohlraums". United States. doi:10.1063/1.871511.
@article{osti_383795,
title = {Indirect-drive radiation uniformity in tetrahedral hohlraums},
author = {Schnittman, J D and Craxton, R S},
abstractNote = {Tetrahedral hohlraums, by which are understood spherical hohlraums with four laser entrance holes (LEH{close_quote}s) placed at or near the vertices of a tetrahedron, are proposed for the National Ignition Facility (NIF) [J. Lindl, Phys. Plasmas {bold 2}, 3933 (1995)] and the upgraded OMEGA laser [T. R. Boehly {ital et} {ital al}., Rev. Sci. Instrum. {bold 66}, 508 (1995)]. All but four of the 48 NIF beams can irradiate a tetrahedral hohlraum, assuming that 72 beam ports are provided to accommodate direct drive. On OMEGA, the target chamber provides an exact tetrahedral symmetry, permitting the irradiation of tetrahedral hohlraums with all 60 beams. Hohlraum designs are optimized using a new three-dimensional view-factor program called Buttercup, which traces all beam paths through the hohlraum and calculates the radiation flux on the capsule for different values of the albedo. Good irradiation uniformity ({approximately}2{percent} rms) can be obtained on the capsule at all times during the implosion, even with identical beam temporal histories, in contrast to the case of cylindrical hohlraums where {open_quote}{open_quote}beam phasing{close_quote}{close_quote} is needed. {copyright} {ital 1996 American Institute of Physics.}},
doi = {10.1063/1.871511},
journal = {Physics of Plasmas},
number = 10,
volume = 3,
place = {United States},
year = {1996},
month = {10}
}