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arXiv · 2007.07774

Scaling laws for direct laser acceleration in a radiation-reaction dominated regime

M. Jirka·M. Vranic·T. Grismayer·L. O. Silva
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Abstract

We study electron acceleration within a sub-critical plasma channel irradiated by an ultra-intense laser pulse ($a_0>100$ or $I>10^{22}~\mathrm{W/cm^2}$). In this regime, radiation reaction significantly alters the electron dynamics. This has an effect not only on the maximum attainable electron energy but also on the phase-matching process between betatron motion and electron oscillations in the laser field. Our study encompasses analytical description, test-particle calculations and 2-dimensional particle-in-cell simulations. We show single-stage electron acceleration to multi-GeV energies within a 0.5 mm-long channel and provide guidelines how to obtain energies beyond 10 GeV using optimal initial configurations. We present the required conditions in a form of explicit analytical scaling laws that can be applied to plan the future electron acceleration experiments.

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M. Jirka, M. Vranic, T. Grismayer, L. O. Silva. 2020-07-15. Scaling laws for direct laser acceleration in a radiation-reaction dominated regime. https://doi.org/10.1088/1367-2630%2Faba653

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