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arXiv · 1608.08120

Nonlinear Breit-Wheeler pair production in a tightly focused laser beam

A. Di Piazza
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Abstract

The only available analytical framework for investigating QED processes in a strong laser field systematically relies on approximating the latter as a plane wave. However, realistic high-intensity laser beams feature much more complex space-time structures than plane waves. Here, we show the feasibility of an analytical framework for investigating strong-field QED processes in laser beams of arbitrary space-time structure by determining the energy spectrum of positrons produced via nonlinear Breit-Wheeler pair production as a function of the background field in the realistic assumption that the energy of the incoming photon is the largest dynamical energy in the problem. A numerical evaluation of the angular resolved positron spectrum shows significant quantitative differences with respect to the analogous result in a plane wave, such that the present results will be also important for the design of upcoming strong laser facilities aiming at measuring this process.

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A. Di Piazza. 2016-11-16. Nonlinear Breit-Wheeler pair production in a tightly focused laser beam. https://doi.org/10.1103/physrevlett.117.213201

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