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arXiv · 1304.2187

Dense electron-positron plasmas and bursts of gamma-rays from laser-generated QED plasmas

C. P. Ridgers·C. S. Brady·R. Duclous·J. G. Kirk·K. Bennett·T. D. Arber·A. R. Bell
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Abstract

In simulations of a 12.5PW laser (focused intensity I = 4x10^23W/cm^2) striking a solid aluminium target 10% of the laser energy is converted to gamma-rays. A dense electron-positron plasma is generated with a maximum density of 10^26/m^3; seven orders of magnitude denser than pure e-e+ plasmas generated with 1PW lasers. When the laser power is increased to 320PW (I = 10^25W/cm^2) 40% of the laser energy is converted to gamma-ray photons and 10% to electron-positron pairs. In both cases there is strong feedback between the QED emission processes and the plasma physics; the defining feature of the new `QED-plasma' regime reached in these interactions.

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C. P. Ridgers, C. S. Brady, R. Duclous, J. G. Kirk, K. Bennett, T. D. Arber, A. R. Bell. 2013-04-08. Dense electron-positron plasmas and bursts of gamma-rays from laser-generated QED plasmas. https://doi.org/10.1063/1.4801513

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