相关论文: Coherent $J/\psi$ photoproduction and polarization…
Photonuclear reactions are induced by the strong electromagnetic field generated by ultrarelativistic heavy ions. These processes have been extensively studied in ultraperipheral collisions. In recent years, the observation of coherent…
Photon-photon reactions and the production of J/$\psi$ meson through photonuclear reactions have been extensively studied in ultra-peripheral heavy-ion collisions, in which the impact parameter is larger than twice the nuclear radius. In…
Recent measurements of J/$\psi$ photoproduction based on data from ultra-peripheral Pb-Pb and p-Pb collisions recorded by the ALICE experiment during Run 2 of the LHC are presented. Photoproduction as a photon-induced process is sensitive…
The photoproduction of heavy vector mesons in the electromagnetic interactions of ultra-relativistic nuclei is sensitive to the gluon distribution in the nucleus and thus to cold nuclear matter effects like shadowing or parton saturation.…
The ALICE collaboration performed the first rapidity-differential measurement of coherent J/$\psi$ photoproduction in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. The J/$\psi$ is detected via…
The ALICE collaboration has made the first measurement at the LHC of J/$\psi$ photoproduction in ultra-peripheral Pb-Pb-collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV. The J/$\psi$ is identified via its dimuon decay in the forward rapidity…
The coherent photoproduction of $\rm{J/\psi}$ and $\rm{\psi'}$ mesons was measured in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\mathrm{NN}}}~=~5.02$ TeV with the ALICE detector. Charmonia are detected in the…
The first measurement of the polarisation of coherently photoproduced J$/\psi$ mesons in ultra-peripheral Pb-Pb collisions, using data at $\sqrt{s_{\rm NN}}$ = 5.02 TeV, is presented. The J/$\psi$ meson is measured via its dimuon decay…
An excess of J/$\psi$ yield at very low transverse momentum ($p_{\rm T} < 0.3$ GeV/$c$), originating from coherent photoproduction, is observed in peripheral and semicentral hadronic Pb$-$Pb collisions at a center-of-mass energy per nucleon…
A significant excess of J/$\psi$ yield at very low transverse momentum ($p_T < 0.3$ GeV/c) was observed by the ALICE and STAR collaborations in peripheral A+A collisions, which points to evidence of coherent photoproduction of J/$\psi$ in…
Lead nuclei, accelerated at the LHC, are sources of strong electromagnetic fields that can be used to measure photon-induced interactions in a new kinematic regime. These interactions can be studied in ultra-peripheral p-Pb and Pb-Pb…
The ALICE experiment measured J/psi photoproduction in Pb+Pb ultraperipheral collisions at sqrt(s_NN) = 2.76 TeV at forward and central rapidity. The coherent J/psi cross section is found to be in good agreement with those models which…
Vector mesons are copiously produced in ultra-peripheral collisions. In these collisions, the impact parameter is larger than the sum of the radii of two projectiles, implying that electromagnetic processes become dominant. The cross…
Ultra-peripheral Pb-Pb collisions, in which the two nuclei pass close to each other, but at an impact parameter greater than the sum of their radii, provide information about the initial state of nuclei. In particular, heavy vector meson…
Ultra-peripheral collisions (UPC) are events characterised by large impact parameters between the two projectiles, larger than the sum of their radii. In UPCs, the protons and ions accelerated by the LHC do not interact via the strong…
Ultra-peripheral collisions of heavy ions provide a unique environment to study the gluon structure of nuclei through photon-induced reactions. In particular, the incoherent photoproduction of J/$\psi$ vector meson is sensitive to…
The cross section for coherent J/psi photoproduction accompanied by at least one neutron on one side of the interaction point and no neutron activity on the other side, X[n]0[n], is measured with the CMS experiment in ultra-peripheral PbPb…
The first LHC measurement on ultra-peripheral heavy-ion collisions was carried out with the ALICE experiment. In this paper, ALICE results on exclusive J/psi studies in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV, in the rapidity region -3.6…
Incoherent and dissociative J/$\psi$ photoproduction is sensitive to fluctuations of the gluonic structure of the target. Thus, the measurement of J/$\psi$ photoproduction of the colliding hadron sheds light on the initial state of QCD and…
A comprehensive analysis of the photoproduction of $J/\Psi$ and $\Upsilon$ mesons in peripheral $PbPb$ collisions at the center - of - mass energies of the Large Hadron Collider (LHC) is performed, considering distinct assumptions for the…