Magnetically driven isentropic compression to multimegabar pressures using shaped current pulses on the Z accelerator

被引：93

作者：

Davis, JP ^{[1
]}

Deeney, C ^{[1
]}

Knudson, MD ^{[1
]}

Lemke, RW ^{[1
]}

Pointon, TD ^{[1
]}

Bliss, DE ^{[1
]}

机构：

[1] Sandia Natl Labs, Albuquerque, NM 87185 USA

来源：

PHYSICS OF PLASMAS | 2005年 / 12卷 / 05期

关键词：

D O I：

10.1063/1.1871954

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

A technique has previously been developed on the Z accelerator [R. B. Spielman , Phys. Plasmas 5, 2105 (1998)] to generate ramped compression waves in condensed matter for equation-of-state studies [C. A. Hall, J. R. Asay, M. D. Knudson, W. A. Stygar, R. B. Spielman, T. D. Pointon, D. B. Reisman, A. Toor, and R. C. Cauble, Rev. Sci. Instrum. 72, 3587 (2001)] by using the Lorentz force to push on solid electrodes rather than to drive a Z pinch. This technique has now been extended to multimegabar pressures by shaping the current pulse on Z to significantly increase the sample thickness through which the compression wave can propagate without forming a shock. Shockless, free-surface velocity measurements from multiple sample thicknesses on a single experiment can be analyzed using a backward integration technique [D. B. Hayes, C. A. Hall, J. R. Asay, and M. D. Knudson, J. Appl. Phys. 94, 2331 (2003)] to extract an isentropic loading curve. At very high pressures, the accuracy of this method is dominated by relative uncertainty in the transit time between two thicknesses. This paper discusses in some detail the issues involved with accurate measurement of a multimegabar isentrope, including experiment design trade-offs and mechanics of pulse shaping on Z. (c) 2005 American Institute of Physics.

引用

页数：7

共 20 条

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