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arXiv · 2212.11578

Worldline instantons for the momentum spectrum of Schwinger pair production in space-time dependent fields

Gianluca Degli Esposti·Greger Torgrimsson
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Abstract

We show how to use the worldline-instanton formalism to calculate the momentum spectrum of the electron-positron pairs produced by an electric field that depends on both space and time. Using the LSZ reduction formula with a worldline representation for the propagator in a spacetime field, we make use of the saddle-point method to obtain a semiclassical approximation of the pair-production spectrum. In order to check the final result, we integrate the spectrum and compare with the results obtained using a previous instanton method for the imaginary part of the effective action.

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Gianluca Degli Esposti, Greger Torgrimsson. 2022-12-22. Worldline instantons for the momentum spectrum of Schwinger pair production in space-time dependent fields. https://doi.org/10.1103/physrevd.107.056019

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