Parton distributions with QED corrections

The NNPDF Collaboration; Richard D. Ball; Valerio Bertone; Stefano Carrazza; Luigi Del Debbio; Stefano Forte; Alberto Guffanti; Nathan P. Hartland; Juan Rojo

doi:10.1016/j.nuclphysb.2013.10.010

arXiv · 1308.0598

Parton distributions with QED corrections

The NNPDF Collaboration·Richard D. Ball·Valerio Bertone·Stefano Carrazza·Luigi Del Debbio·Stefano Forte·Alberto Guffanti·Nathan P. Hartland·Juan Rojo

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Abstract

We present a set of parton distribution functions (PDFs), based on the NNPDF2.3 set, which includes a photon PDF, and QED contributions to parton evolution. We describe the implementation of the combined QCD+QED evolution in the NNPDF framework. We then provide a first determination of the full set of PDFs based on deep-inelastic scattering data and LHC data for W and Z/gamma* Drell-Yan production, using leading-order QED and NLO or NNLO QCD. We compare the ensuing NNPDF2.3QED PDF set to the older MRST2004QED set. We perform a preliminary investigation of the phenomenological implications of NNPDF2.3QED: specifically, photon-induced corrections to direct photon production at HERA, and high-mass dilepton and W pair production at the LHC.

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The NNPDF Collaboration, Richard D. Ball, Valerio Bertone, Stefano Carrazza, Luigi Del Debbio, Stefano Forte, Alberto Guffanti, Nathan P. Hartland, Juan Rojo. 2013-08-02. Parton distributions with QED corrections. https://doi.org/10.1016/j.nuclphysb.2013.10.010

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