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arXiv · 1411.3237

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

Tristan Dennen·Ciaran Williams
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Abstract

We present Next-to-Leading Order (NLO) predictions for $γγγγ$ 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 $4γ$ signal at colliders, both for Run II of the LHC and at future machines. Our results are implemented in MCFM.

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Tristan Dennen, Ciaran Williams. 2014-11-12. Four photon production at the LHC: an application of 2->4 analytic unitarity. https://doi.org/10.1103/physrevd.91.054012

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