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arXiv · 1308.6246

Observation of Self-Sustaining Relativistic Ionization Wave Launched by Sheath Field

M. W. McCormick·A. V. Arefiev·H. J. Quevedo·R. D. Bengtson·T. Ditmire
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Abstract

We present experimental evidence supported by simulations of a relativistic ionization wave launched into surrounding gas by the sheath field of a plasma filament with high energy electrons. Such filament is created by irradiating a clustering gas jet with a short pulse laser ($\sim$115 fs) at a peak intensity of $5 \times 10^{17}$ W/cm$^2$. We observe an ionization wave propagating radially through the gas for about 2 ps at 0.2-0.5 $c$ after the laser has passed, doubling the initial radius of the filament. The gas is ionized by the sheath field, while the longevity of the wave is explained by a moving field structure that traps the high energy electrons near the boundary, maintaining a strong sheath field despite the significant expansion of the plasma.

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M. W. McCormick, A. V. Arefiev, H. J. Quevedo, R. D. Bengtson, T. Ditmire. 2013-08-28. Observation of Self-Sustaining Relativistic Ionization Wave Launched by Sheath Field. https://doi.org/10.1103/physrevlett.112.045002

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