Measurement of prompt photon production in root s(NN)=8.16 TeV p Pb collisions with ATLAS

Aaboud, M.; Aad, G.; Abbott, B.; Abbott, D. C.; Abdinov, O.; Abeloos, B.; Abhayasinghe, D. K. und Abidi, S. H. (2019): Measurement of prompt photon production in root s(NN)=8.16 TeV p Pb collisions with ATLAS. In: Physics Letters B, Bd. 796: S. 230-252

Abstract

The inclusive production rates of isolated, prompt photons in p Pb collisions at root s(NN) = 8.16 TeV are studied with the ATLAS detector at the Large Hadron Collider using a dataset with an integrated luminosity of 165 nb(-1) recorded in 2016. The cross-section and nuclear modification factor R-p pb are measured as a function of photon transverse energy from 20 GeV to 550 GeV and in three nucleon-nucleon centre-of-mass pseudorapidity regions, (-2.83, -2.02), (-1.84, 0.91), and (1.09, 1.90). The cross-section and R-p pb values are compared with the results of a next-to-leading-order perturbative QCD calculation, with and without nuclear parton distribution function modifications, and with expectations based on a model of the energy loss of partons prior to the hard scattering. The data disfavour a large amount of energy loss and provide new constraints on the parton densities in nuclei. (C) 2019 The Author. Published by Elsevier B.V.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 0370-2693
• Sprache: Englisch