Calculation and analysis of the vacuum polarisation signal in a three-beam setup

Abstract: We report the development of an efficient method for calculating the number and characteristics of photons emitted by a vacuum polarised by overlapping focused laser pulses. The dependence of the signal on the focusing and polarisation of pulses is studied and optimised, and the possibility of its detection on the XCELS multipetawatt facility is substantiated.

Keywords: vacuum polarisation, three-beam setup, multipetawatt laser pulses.