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Title: High planarity x-ray drive for ultra-fast shockless-compression experiments

Abstract

A spatially-planar ({Delta}time/time {approx} 0.2%) longitudinal stress drive extending over millimeter scale lengths is used to shocklessly compress an aluminum sample to a peak stress of 210 GPa over nanosecond timescales. Direct laser irradiation onto the inner wall of an Au halfraum creates an x ray distribution with a near-uniform blackbody temperature of up to 137eV. The x rays ablate material from a low-Z foil in a region of planarity closely matched to the diameter of the halfraum. The resultant ablatively-driven shock is converted into a ramp-stress-wave in a secondary aluminum target through unloading across an intermediate vacuum-gap. Higher peak ramp stresses and shorter associated rise-times result from increasing input laser energy. Ramp-compression experiments can provide single shot equation-of-state data close to the isentrope, information on the kinetics of phase transformations and material strength at high pressures.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
952078
Report Number(s):
UCRL-JRNL-229932
Journal ID: ISSN 1070-664X; PHPAEN; TRN: US0902389
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas, vol. 14, no. 5, April 4, 2007, pp. 057105; Journal Volume: 14; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; ALUMINIUM; DISTRIBUTION; IRRADIATION; KINETICS; LASERS; PHASE TRANSFORMATIONS; STRESSES; TARGETS; UNLOADING

Citation Formats

Smith, R, Pollaine, S, Moon, S, Lorenz, K T, Celliers, P, Eggert, J, Park, H, and Collins, G. High planarity x-ray drive for ultra-fast shockless-compression experiments. United States: N. p., 2007. Web.
Smith, R, Pollaine, S, Moon, S, Lorenz, K T, Celliers, P, Eggert, J, Park, H, & Collins, G. High planarity x-ray drive for ultra-fast shockless-compression experiments. United States.
Smith, R, Pollaine, S, Moon, S, Lorenz, K T, Celliers, P, Eggert, J, Park, H, and Collins, G. Tue . "High planarity x-ray drive for ultra-fast shockless-compression experiments". United States. doi:. https://www.osti.gov/servlets/purl/952078.
@article{osti_952078,
title = {High planarity x-ray drive for ultra-fast shockless-compression experiments},
author = {Smith, R and Pollaine, S and Moon, S and Lorenz, K T and Celliers, P and Eggert, J and Park, H and Collins, G},
abstractNote = {A spatially-planar ({Delta}time/time {approx} 0.2%) longitudinal stress drive extending over millimeter scale lengths is used to shocklessly compress an aluminum sample to a peak stress of 210 GPa over nanosecond timescales. Direct laser irradiation onto the inner wall of an Au halfraum creates an x ray distribution with a near-uniform blackbody temperature of up to 137eV. The x rays ablate material from a low-Z foil in a region of planarity closely matched to the diameter of the halfraum. The resultant ablatively-driven shock is converted into a ramp-stress-wave in a secondary aluminum target through unloading across an intermediate vacuum-gap. Higher peak ramp stresses and shorter associated rise-times result from increasing input laser energy. Ramp-compression experiments can provide single shot equation-of-state data close to the isentrope, information on the kinetics of phase transformations and material strength at high pressures.},
doi = {},
journal = {Physics of Plasmas, vol. 14, no. 5, April 4, 2007, pp. 057105},
number = 5,
volume = 14,
place = {United States},
year = {Tue Apr 03 00:00:00 EDT 2007},
month = {Tue Apr 03 00:00:00 EDT 2007}
}
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