Speaker
Jaroslav Adam
(Czech Technical University in Prague, Creighton University, Omaha)
Description
Ultra-relativistic heavy ions generate strong electromagnetic fields, which
offer the possibility to study photon-photon, photon-nucleus and photon-proton
processes at the LHC in ultra-peripheral p-Pb and Pb-Pb collisions (UPC).
Exclusive photoproduction of vector mesons is sensitive to the gluon distribution
of the interacting target (proton or nucleus) whereas exclusive production of lepton pairs
in the photon-photon interactions in Pb-Pb probes quantum electrodynamics
with a large coupling constant.
Here we present ALICE measurements of J/psi vector meson photoproduction in p-Pb UPC
at sqrt(s_NN) = 5.02 TeV. We report the results in several intervals of the photon-proton
center-of-mass energy which is constrained by the the rapidity of the vector meson.
Furthermore, we present results on exclusive electron-positron pair production
in photon-photon collisions in Pb-Pb UPC at sqrt(s_NN) = 2.76 TeV.
Primary author
Jaroslav Adam
(Czech Technical University in Prague, Creighton University, Omaha)
