Four photon production at the LHC: an application of 2->4 analytic unitarity

TL;DR

This paper provides precise NLO predictions for four-photon production at the LHC using advanced analytic unitarity techniques, including photon fragmentation effects, and offers a stable Monte Carlo implementation for collider analyses.

Contribution

It introduces a fully analytic calculation of four-photon production at NLO with improved methods for three-mass triangle coefficients, enhancing accuracy and stability.

Findings

NLO predictions for 4-photon final states at the LHC

Implementation of a stable Monte Carlo code in MCFM

Analysis of the 4γ signal at current and future colliders

Abstract

We present Next-to-Leading Order (NLO) predictions for $\gamma\gamma\gamma\gamma$ final states, including the effects of photon fragmentation. Our results are calculated fully analytically using the techniques of $D$-dimensional unitarity, and we discuss some refinements to existing methods, focusing particularly on the role of three-mass triangle coefficients. Using these techniques we are able to produce a numerically stable Monto Carlo code that runs fully in double precision. We investigate the $4\gamma$ signal at colliders, both for Run II of the LHC and at future machines. Our results are implemented in MCFM.