Light-by-light scattering: asymptotic expansions, Coulomb resummation and NLO corrections

TL;DR

This paper refines theoretical predictions for light-by-light scattering in QED by improving amplitude calculations, performing Coulomb resummation, and providing a new event generator for simulations.

Contribution

It introduces improved amplitude calculations, Coulomb resummation techniques, and a new Monte Carlo event generator for light-by-light scattering.

Findings

Enhanced accuracy of LbL cross section predictions.

Implementation of Coulomb resummation in the threshold region.

Development of the LbLatNLO event generator.

Abstract

Light-by-light (LbL) scattering is one of the earliest predictions of quantum electrodynamics (QED). Interest in this process has been renewed following its experimental observation at the LHC and the prospects of future measurements at free-electron laser facilities. In this paper, we refine theoretical predictions for LbL scattering by improving the full fermion-mass-dependent two-loop QCD and QED helicity amplitudes using high- and low-energy asymptotic expansions, and by performing Coulomb resummation in the threshold region. We present state-of-the-art predictions for LbL cross sections in the Standard Model and provide a new event generator, LbLatNLO, for Monte Carlo simulations of LbL scattering.