Prompt photon production and photon-jet correlations at the LHC

Abstract

Next-to-leading order predictions matched to parton showers are compared with recent ATLAS data on inclusive photon production and CMS data on associated photon and jet production in pp and pPb collisions at different centre-of-mass energies of the LHC. We find good agreement and, as expected, considerably reduced scale uncertainties compared to previous theoretical calculations. Predictions are made for the ratio of inclusive photons over decay photons $R_{\gamma }$, an important quantity to evaluate the significance of additional photon sources, e.g. thermal radiation from a Quark-Gluon-Plasma, and for distributions in the parton momentum fraction in lead ions $x_{\mathrm{Pb}}^{\mathrm{obs}}$, that could be determined by ALICE, ATLAS, CMS and LHCb in ongoing analyses of photon+jet production in pPb collisions at $\sqrt{s_{NN}}=5.02$ TeV. These data should have an important impact on the determination of nuclear effects such as shadowing at low $x$.

20 pages, 13 figures

References in corpus (11)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Parton distributions from high-precision collider data
• EPPS16: Nuclear parton distributions with LHC data
• A new critical study of photon production in hadronic collisions
• Measurement of the differential photon+ c-jet cross section and the ratio of differential photon+ c and photon+ b cross sections in proton-antiproton collisions at sqrt(s) = 1.96 TeV
• Measurement of the cross section for isolated-photon plus jet production in $pp$ collisions at $\sqrt{s}=13$ TeV using the ATLAS detector
• $Z\gamma$ production at NNLO including anomalous couplings
• Nuclear parton density functions from jet production in DIS at the EIC
• W gamma production in hadronic collisions using the POWHEG+MiNLO method
• New information on photon fragmentation functions

Cited by in corpus (8)

• Direct photon production at low transverse momentum in proton-proton collisions at $\sqrt{s}$ = 2.76 and 8 TeV
• Advancing MiNNLO${}_{\mathrm{PS}}$ to diboson processes: $Z\gamma$ production at NNLO+PS
• Isolated photon-hadron production in high energy $pp$ and $pA$ collisions at RHIC and LHC
• Measurement of the inclusive isolated-photon cross section in $pp$ collisions at $\sqrt{s}=13$ TeV using 36 fb${}^{-1}$ of ATLAS data
• Prompt photon production in high-energy $pA$ collisions at forward rapidity
• Probing nuclear modifications of parton distribution functions through the isolated prompt photon production at the LHC
• Isolated photon production in $pp$ collisions at forward rapidities and high multiplicity events
• Nuclear gluons at RHIC in a multi-observable approach