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arXiv · 2508.20775

Progress in NLO Calculations for gamma-gamma Physics

Hua-Sheng Shao·Lukas Simon
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Abstract

With the advent of precision measurements of photon-fusion processes in ultraperipheral collisions (UPCs) at facilities, such as RHIC and the LHC, the inclusion of higher-order corrections has become essential. While automated frameworks already make NLO corrections feasible for parton-parton scattering processes, no comparable tools had previously been available for UPC processes in two-photon collisions. In these proceedings, we review some recent explicit NLO computations and present the updated gamma-UPC+MadGraph5_aMC@NLO framework, the first automated software that enables NLO-accurate predictions for photon-photon processes in UPCs.

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Hua-Sheng Shao, Lukas Simon. 2025-08-28. Progress in NLO Calculations for gamma-gamma Physics. https://arxiv.org/abs/2508.20775

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