The Production of Isolated Photons in PbPb and pp Collisions at √sNN = 5.02 TeV

Journal of High Energy Physics 2020
Viesturs Veckalns

The transverse energy (ETγ) spectra of photons isolated from other particles are measured using proton-proton (pp) and lead-lead (PbPb) collisions at the LHC at sNN = 5.02 TeV with integrated luminosities of 27.4 pb−1 and 404 μb−1 for pp and PbPb data, respectively. The results are presented for photons with 25 <ETγ< 200 GeV in the pseudorapidity range |η| < 1.44, and for different centrality intervals for PbPb collisions. Photon production in PbPb collisions is consistent with that in pp collisions scaled by the number of binary nucleon-nucleon collisions, demonstrating that photons do not interact with the quark-gluon plasma. Therefore, isolated photons can provide information about the initial energy of the associated parton in photon+jet measurements. The results are compared with predictions from the next-to-leading-order jetphox generator for different parton distribution functions (PDFs) and nuclear PDFs (nPDFs). The comparisons can help to constrain the nPDFs global fits. [Figure not available: see fulltext.]

Keywords
Hadron-Hadron scattering (experiments) | Heavy-ion collision | Photon production
DOI
10.1007/JHEP07(2020)116
Hyperlink
https://link.springer.com/article/10.1007%2FJHEP07%282020%29116

Veckalns, V., CERN international group of authors. The Production of Isolated Photons in PbPb and pp Collisions at √sNN = 5.02 TeV. Journal of High Energy Physics, 2020, Vol. 2020, No. 7, Article number 116. ISSN 1126-6708. e-ISSN 1029-8479. Available from: doi:10.1007/JHEP07(2020)116

Publication language
English (en)