2026-10-19T01:43:55Zhttps://ebyu-rdlopen.rawdatalibrary.net/oai/requestoai:ebyu-rdlopen.rawdatalibrary.net:ebyu/118592026-10-18T20:26:51Zopenairedrivercom_ebyu_10000col_ebyu_10001Probing Small Bjorken-x Nuclear Gluonic Structure via Coherent J=ψ Photoproduction in Ultraperipheral Pb-Pb Collisions at √sNN = 5.02 TeVTumasyan, A.Adam, W.Andrejkovic, J.W.Bergauer, T.Chatterjee, S.Damanakis, K.Dragicevic, M.Escalante Del Valle, A.Hussain, P.S.Jeitler, M.Krammer, N.Lechner, L.Liko, D.Mikulec, I.Schieck, J.Schöfbeck, R.Schwarz, D.Sonawane, M.Templ, S.Waltenberger, W.Wulz, C.-E.Darwish, M.R.Janssen, T.Kello, T.Van Mechelen, P.Bols, E.S.D’Hondt, J.De Moor, A.Delcourt, M.El Faham, H.Lowette, S.Morton, A.Müller, D.Sahasransu, A.R.Tavernier, S.Van Doninck, W.Van Putte, S.Vannerom, D.Clerbaux, B.Dansana, S.De Lentdecker, G.Favart, L.Hohov, D.Jaramillo, J.Lee, K.Mahdavikhorrami, M.Makarenko, I.Malara, A.Paredes, S.Pétré, L.Binary alloysGermanium alloysHeavy ionsIon exchangeLead alloysTellurium compoundsCenter-of-mass energiesCentre-of-mass energiesHeaviest nucleiHeavy ion interactionsIntegrated luminosityLead collisionsNucleon-nucleonPb-Pb collisionsPhotoproductionsRelativistic heavy ionsarticlecontrolled studydiagnosisPhotonsQuasireal photons exchanged in relativistic heavy ion interactions are powerful probes of the gluonic structure of nuclei. The coherent J=ψ photoproduction cross section in ultraperipheral lead-lead collisions is measured as a function of photon-nucleus center-of-mass energies per nucleon (WPb γN) over a wide range of 40 < WPb γN < 400 GeV. Results are obtained using data at the nucleon-nucleon center-of-mass energy of 5.02 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 1.52 nb−1. The cross section is observed to rise rapidly at low WPb γN, and plateau above WPb γN ≈ 40 GeV, up to 400 GeV, entering a new regime of small Bjorken-x (≈6 × 10−5) gluons being probed in a heavy nucleus. The observed energy dependence is not predicted by current quantum chromodynamic models. © 2023 CERN, for the CMS Collaboration.American Physical Society2023Articlehttps://rdlopen.rawdatalibrary.net/r/ebyu/11859https://doi.org/10.1103/physrevlett.131.2623010031-9007enPhysical Review Lettersinfo:eu-repo/semantics/openAccessinfo:eu-repo/semantics/articlehttps://ebyu-rdlopen.rawdatalibrary.net/tr/items/ebyu/11859