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arXiv · 1603.02663

Predictions for diphoton production at the LHC through NNLO in QCD

John M. Campbell·R. Keith Ellis·Ye Li·Ciaran Williams
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Abstract

In this paper we present a next-to-next-to-leading order (NNLO) calculation of the process $pp\rightarrow γγ$ that we have implemented into the parton level Monte Carlo code MCFM. We do not find agreement with the previous calculation of this process in the literature. In addition to the $\mathcal{O}(α_s^2)$ corrections present at NNLO, we include some effects arising at $\mathcal{O}(α_s^3)$, namely those associated with gluon-initiated closed fermion loops. We investigate the role of this process in the context of studies of QCD at colliders and as a background for searches for new physics, paying particular attention to the diphoton invariant mass spectrum. We demonstrate that the NNLO QCD prediction for the shape of this spectrum agrees well with functional forms used in recent data-driven fits.

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John M. Campbell, R. Keith Ellis, Ye Li, Ciaran Williams. 2021-09-14. Predictions for diphoton production at the LHC through NNLO in QCD. https://doi.org/10.1007/jhep07(2016)148

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