TY - JOUR AU - ATLAS Collaboration (Aaboud, M. et al AU - Alvarez Piqueras, D. AU - Aparisi Pozo, J. A. AU - Bailey, A. J. AU - Barranco Navarro, L. AU - Cabrera Urban, S. AU - Castillo, F. L. AU - Castillo Gimenez, V. AU - Cerda Alberich, L. AU - Costa, M. J. AU - Escobar, C. AU - Estrada Pastor, O. AU - Ferrer, A. AU - Fiorini, L. AU - Fullana Torregrosa, E. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gonzalez de la Hoz, S. AU - Higon-Rodriguez, E. AU - Jimenez Pena, J. AU - Lacasta, C. AU - Lozano Bahilo, J. J. AU - Madaffari, D. AU - Mamuzic, J. AU - Marti-Garcia, S. AU - Melini, D. AU - MiƱano, M. AU - Mitsou, V. A. AU - Rodriguez Bosca, S. AU - Rodriguez Rodriguez, D. AU - Ruiz-Martinez, A. AU - Salt, J. AU - Santra, A. AU - Soldevila, U. AU - Sanchez, J. AU - Valero, A. AU - Valls Ferrer, J. A. AU - Vos, M. PY - 2019 DA - 2019// TI - Measurement of prompt photon production in root s(NN)=8.16 TeV p Pb collisions with ATLAS T2 - Phys. Lett. B JO - Physics Letters B SP - 230 EP - 252 VL - 796 PB - Elsevier AB - 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. SN - 0370-2693 UR - https://arxiv.org/abs/1903.02209 UR - https://doi.org/10.1016/j.physletb.2019.07.031 DO - 10.1016/j.physletb.2019.07.031 LA - English N1 - WOS:000483426200031 ID - ATLASCollaborationAaboud_etal2019 ER -