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arXiv · 1307.5198

Pair plasma cushions in the hole-boring scenario

J. G. Kirk·A. R. Bell·C. P. Ridgers
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Abstract

Pulses from a 10 PW laser are predicted to produce large numbers of gamma-rays and electron-positron pairs on hitting a solid target. However, a pair plasma, if it accumulates in front of the target, may partially shield it from the pulse. Using stationary, one-dimensional solutions of the two-fluid (electron-positron) and Maxwell equations, including a classical radiation reaction term, we examine this effect in the hole-boring scenario. We find the collective effects of a pair plasma "cushion" substantially reduce the reflectivity, converting the absorbed flux into high-energy gamma-rays. There is also a modest increase in the laser intensity needed to achieve threshold for a non-linear pair cascade.

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J. G. Kirk, A. R. Bell, C. P. Ridgers. 2013-08-06. Pair plasma cushions in the hole-boring scenario. https://doi.org/10.1088/0741-3335%2F55%2F9%2F095016

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