The production of isolated photons in PbPb and pp collisions at √sNN = 5.02 TeV


Date

2020

Publication Type

Journal Article

ETH Bibliography

yes

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Data

Abstract

The transverse energy (EγT) 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 < EγT < 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.

Publication status

published

Editor

Book title

Volume

2020 (7)

Pages / Article No.

116

Publisher

Springer

Event

Edition / version

Methods

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Subject

Hadron-Hadron scattering (experiments); Heavy-ion collision; Photon production

Organisational unit

03593 - Dissertori, Günther / Dissertori, Günther check_circle
03904 - Wallny, Rainer / Wallny, Rainer check_circle
08803 - Grab, Christoph (Tit.Prof.) check_circle
09720 - de Cosa, Annapaola / de Cosa, Annapaola check_circle

Notes

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