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arXiv · 1610.06404

Ultra-bright GeV photon source via controlled electromagnetic cascades in laser-dipole waves

A. Gonoskov·A. Bashinov·S. Bastrakov·E. Efimenko·A. Ilderton·A. Kim·M. Marklund·I. Meyerov·A. Muraviev·A. Sergeev
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Abstract

One aim of upcoming high-intensity laser facilities is to provide new high-flux gamma-ray sources. Electromagnetic cascades may serve for this, but are known to limit both field strengths and particle energies, restricting efficient production of photons to sub-GeV energies. Here we show how to create a directed GeV photon source, enabled by a controlled interplay between the cascade and anomalous radiative trapping. Using advanced 3D QED particle-in-cell (PIC) simulations and analytic estimates, we show that the concept is feasible for planned peak powers of 10 PW level. A higher peak power of 40 PW can provide $10^9$ photons with GeV energies in a well-collimated 3 fs beam, achieving peak brilliance ${9 \times 10^{24}}$ ph s$^{-1}$mrad$^{-2}$mm$^{-2}$/0.1${\%}$BW. Such a source would be a powerful tool for studying fundamental electromagnetic and nuclear processes.

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A. Gonoskov, A. Bashinov, S. Bastrakov, E. Efimenko, A. Ilderton, A. Kim, M. Marklund, I. Meyerov, A. Muraviev, A. Sergeev. 2016-10-20. Ultra-bright GeV photon source via controlled electromagnetic cascades in laser-dipole waves. https://doi.org/10.1103/physrevx.7.041003

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