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arXiv · 1712.09237

Leveraging extreme laser-driven magnetic fields for gamma-ray generation and pair production

Oliver Jansen·Tao Wang·David Stark·Toma Toncian·Alexey Arefiev
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Abstract

The ability of an intense laser pulse to propagate in a classically over-critical plasma through the phenomenon of relativistic transparency is shown to facilitate the generation of strong plasma magnetic fields. Particle-in-cell simulations demonstrate that these fields significantly enhance the radiation rates of the laser-irradiated electrons, and furthermore they collimate the emission so that a directed and dense beam of multi-MeV gamma-rays is achievable. This capability can be exploited for electron-positron pair production via the linear Breit-Wheeler process by colliding two such dense beams. Presented simulations show that more than $10^3$ pairs can be produced in such a setup, and the directionality of the positrons can be controlled by the angle of incidence between the beams.

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Oliver Jansen, Tao Wang, David Stark, Toma Toncian, Alexey Arefiev. 2017-12-26. Leveraging extreme laser-driven magnetic fields for gamma-ray generation and pair production. https://doi.org/10.1088/1361-6587/aab222

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