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arXiv · 1510.02301

Generation of high-energy electron-positron beams in the collision of a laser-accelerated electron beam and a multi-petawatt laser

Mathieu Lobet·Xavier Davoine·Emmanuel d'Humières·Laurent Gremillet
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Abstract

Generation of antimatter via the multiphoton Breit-Wheeler process in an all-optical scheme will be made possible on forthcoming high-power laser facilities through the collision of wakefield-accelerated GeV electrons with a counter-propagating laser pulse with $10^{22}$-$10^{23}$ $\mathrm{Wcm}^{-2}$ peak intensity. By means of integrated 3D particle-in-cell simulations, we show that the production of positron beams with 0.1-1 nC total charge, 100-400 MeV mean energy and 0.01-0.1 rad divergence is within the reach of soon-to-be-available laser systems. The variations of the positron beam's properties with respect to the laser parameters are also examined.

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Mathieu Lobet, Xavier Davoine, Emmanuel d'Humières, Laurent Gremillet. 2015-10-12. Generation of high-energy electron-positron beams in the collision of a laser-accelerated electron beam and a multi-petawatt laser. https://doi.org/10.1103/physrevstab.20.043401

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