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arXiv · 1708.00298

Scaling laws for positron production in laser--electron-beam collisions

T. G. Blackburn·A. Ilderton·C. D. Murphy·M. Marklund
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Abstract

Showers of $γ$-rays and positrons are produced when a high-energy electron beam collides with a super-intense laser pulse. We present scaling laws for the electron beam energy loss, the $γ$-ray spectrum, and the positron yield and energy that are valid in the non-linear, radiation-reaction--dominated regime. As an application we demonstrate that by employing the collision of a $>$GeV electron beam with a laser pulse of intensity $>5\times10^{21}\,\text{Wcm}^{-2}$, today's high-intensity laser facilities are capable of producing $O(10^4)$ positrons per shot via light-by-light scattering.

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T. G. Blackburn, A. Ilderton, C. D. Murphy, M. Marklund. 2017-08-16. Scaling laws for positron production in laser--electron-beam collisions. https://doi.org/10.1103/physreva.96.022128

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