Inclusive and diffractive open charm photoproduction in ultraperipheral collisions at the LHC

by Anna Stasto

Wednesday 29 Apr 2026, 14:30 → 15:30 Europe/Rome

Abstract:

      Ultraperipheral collisions (UPCs) of nuclei at high energies offer unique opportunity to explore
the nuclear structure in a clean environment. UPCs occur when two nuclei scatter at impact parameters that exceed the sum of nuclear radii.  In UPC
processes involving heavy quarks, large scale provided by the mass of the heavy quark and transverse momentum allows for perturbative description
of the process, and thus such processes can serve as good probes of the nuclear structure. I will present the calculation of the  inclusive D0
production cross section in UPC PbPb collisions at the LHC using the Generalized photon-nucleus FONLL framework. In this approach the heavy quark
production is computed using the FONLL framework developed previously by Cacciari-Frixione-Nason for ep collisions,  and includes additional
electromagnetic corrections to describe the photoproduction cross section in UPC heavy ion collisions. The calculations are validated against the
D* photoproduction cross section from HERA. The predictions for D0 cross section as a function of rapidity and transverse momentum of the D0 meson
are presented and compared to the results from UPC collisions recently measured by CMS experiment.  Results of the calculations for the diffractive
component for the charm production in UPCs will also be  shown based on the model of the leading twist shadowing. In addition,  predictions for the
inclusive and diffractive charm photoproduction in proton-nucleus UPC collisions will be presented.