Dynamics of single and double argon gas puff Z-pinches on the CESZAR fast 500-kA Linear Transformer Driver

ORAL

Abstract

Gas puff Z-pinches1 are a well-established X-ray source and hold significant potential for thermonuclear fusion. Implosions on fast drivers, like CESZAR (500kA in 160ns) are susceptible to the Magneto Rayleigh-Taylor Instability (MRTI) limiting their utility in applications. We report on a systematic investigation of the snowplow stabilization2 method for mitigating MRTI growth by studying the dynamics of double and single gas puff loads. We compared instability growth in argon liner on argon target, argon liner on deuterium target and hollow argon gas puffs on the CESZAR Linear Transformer Driver. We employed a time-gated XUV pinhole camera to describe the effect of this mitigation technique on implosion dynamics and filtered photodiodes were used to determine the effects on X-ray production. To complement experimental findings, 2-D MHD simulations were performed with the Multiphysics FLASH code to infer the effect of the load structure on pinch density and ion temperature. Results show that an addition of the target improves the stability of the pinch.

Publication: [1] J. L. Giuliani and R. J. Commisso, "A Review of the Gas-Puff Z-Pinch as an X-Ray and Neutron Source," IEEE Transactions on Plasma Science, vol. 43, no. 8, pp. 2385–2453, 2015, doi: 10.1109/TPS.2015.2451157.
[2] S. M. Gol'berg and A. L. Velikovich, "Suppression of Rayleigh-Taylor instability by the snowplow mechanism," Physics of Fluids B, vol. 5, no. 4, pp. 1164–1172, 1993, doi: 10.1063/1.860974.

Presenters

  • Apsara Madonna Williams

    University of California, San Diego

Authors

  • Apsara Madonna Williams

    University of California, San Diego

  • Victor Tranchant

    University of Rochester

  • Fabio Conti

    General Atomics

  • Oren Yang

    University of California, San Diego

  • Kimberly Inzunza

    University of California, San Diego, Center for Energy Research, Univ. of California San Diego La Jolla, CA 92093 USA

  • Robert Beattie-Rossberg

    University of California, San Diego

  • Robert Beattie-Rossberg

    University of California, San Diego

  • Petros Tzeferacos

    University of Rochester

  • Farhat N Beg

    University of California, San Diego, UC San Diego