Photoproduction of low-$p_{\mathrm{T}}$ J/$\psi$ from peripheral to central Pb$-$Pb collisions at 5.02 TeV

Abstract

An excess of J/$\psi$ yield at very low transverse momentum ($p_{\mathrm{T}}<0.3$ GeV/$c$), originating from coherent photoproduction, is observed in peripheral and semicentral hadronic Pb$-$Pb collisions at a center-of-mass energy per nucleon pair of $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. The measurement is performed with the ALICE detector via the dimuon decay channel at forward rapidity ($2.5<y<4$). The nuclear modification factor at very low $p_{\mathrm{T}}$ and the coherent photoproduction cross section are measured as a function of centrality down to the 10% most central collisions. These results extend the previous study at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV, confirming the clear excess over hadronic production in the $p_{\mathrm{T}}$ range 0$-$0.3 GeV/$c$ and the centrality range 70$-$90%, and establishing an excess with a significance greater than 5$\sigma$ also in the 50$-$70% and 30$-$50% centrality ranges. The results are compared with earlier measurements at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV and with different theoretical predictions aiming at describing how coherent photoproduction occurs in hadronic interactions with nuclear overlap.

arXiv comment22 pages, 4 captioned figures, 3 tables, authors from page 17, published version, figures at http://alice-publications.web.cern.ch/node/7890

References in corpus (42)

• Performance of the ALICE Experiment at the CERN LHC
• The Physics of Ultraperipheral Collisions at the LHC
• (Non)Thermal Aspects of Charmonium Production and a New Look at J/$\psi$ Suppression
• EPPS16: Nuclear parton distributions with LHC data
• Enhanced J/Psi Production in Deconfined Quark Matter
• Measurements of Strange Particle Production in $p+p$ Collisions at $\sqrt{s}$= 200 GeV
• STARlight: A Monte Carlo simulation program for ultra-peripheral collisions of relativistic ions
• Medium Modifications and Production of Charmonia at LHC
• Charmonium and $e^{+}{e}^{-}$ pair photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$=2.76 TeV
• Centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Centrality, rapidity and transverse momentum dependence of $J/\psi$ suppression in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$=2.76 TeV
• Coherent J/$\psi$ photoproduction in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• J/psi Transverse Momentum Distribution in High Energy Nuclear Collisions
• J/$\psi$ suppression at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Coherent J/psi photoproduction in ultra-peripheral PbPb collisions at sqrt(s[NN]) = 2.76 TeV with the CMS experiment
• Measurement of an excess in the yield of J/$\psi$ at very low $p_{\mathrm{T}}$ in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Evidence for charmonium generation at the phase boundary in ultra-relativistic nuclear collisions
• Imaging the nucleus with high-energy photons
• Measurement of the cross section for electromagnetic dissociation with neutron emission in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV
• Coherent and incoherent $J/\psi$ photonuclear production in an energy-dependent hot-spot model
• Low-$p_T$ $e^{+}{e}^{-}$ pair production in Au$+$Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and U$+$U collisions at $\sqrt{s_{NN}}$ = 193 GeV at STAR
• Evidence for nuclear gluon shadowing from the ALICE measurements of PbPb ultraperipheral exclusive J/ψ production
• Coherent J/$\psi$ photoproduction at forward rapidity in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Prompt and nonprompt J/$\psi$ production and nuclear modification in $p$Pb collisions at $\sqrt{s_{\text{NN}}}=8.16$ TeV
• Observation of centrality-dependent acoplanarity for muon pairs produced via two-photon scattering in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with the ATLAS detector
• Progress in the Glauber model at collider energies
• First measurement of the $|\text{t}|$-dependence of coherent $J/\psi$ photonuclear production
• Measurement of prompt and nonprompt J/psi production in pp and pPb collisions at sqrt(s[NN]) = 5.02 TeV
• Coherent J/$\psi$ photoproduction in hadronic heavy-ion collisions
• Energy dependence of forward-rapidity J/$\psi$ and $\psi (2S)$ production in pp collisions at the LHC
• Centrality and transverse momentum dependence of inclusive J/$\psi$ production at midrapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Observation of excess J/$\psi$ yield at very low transverse momenta in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}=$ 200 GeV and U+U collisions at $\sqrt{s_{\mathrm{NN}}}=$ 193 GeV
• Small $x$ gluon shadowing from LHC data on coherent $J/\psi$ photoproduction
• Photoproduction of $J/\psi$ mesons in peripheral and semi-central heavy ion collisions
• Nuclear suppression from coherent $J/\psi$ photoproduction at the Large Hadron Collider
• Charmonium Coherent Photoproduction and Hadroproduction with Effects of Quark Gluon Plasma
• Dilepton Radiation in Heavy-Ion Collisions at Small Transverse Momentum
• Prompt and non-prompt J/$\psi$ production and nuclear modification at mid-rapidity in p-Pb collisions at $\sqrt{s_{\text{NN}}}=5.02$ TeV
• Inclusive quarkonium production in pp collisions at $\sqrt{s}=5.02$ TeV
• $J/\psi$ photo-production in Pb-Pb peripheral collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5 TeV
• Heavy Mesons Photoproduction in Peripheral AA Collisions
• Regge phenomenology and coherent photoproduction of charmonium in peripheral heavy ion collisions

Cited by in corpus (4)

• The ALICE experiment: a journey through QCD
• Properties of the QCD Matter: A Review of Selected Results from the ALICE Experiment
• Measurements of inclusive J/$\psi$ production at midrapidity and forward rapidity in Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• $\psi (2S)$ suppression in Pb-Pb collisions at the LHC