Isolated photon production in $pp$ collisions at forward rapidities and high multiplicity events

The production of isolated photons in high multiplicity events is investigated considering the Color Glass Condensate (CGC) formalism. The associated cross-section for proton - proton collisions is estimated considering three distinct solutions of the Balitsky - Kovchegov (BK) equation and predictions for the normalized photon yield as a function of the multiplicities of co - produced charged particles are presented. We predict the increasing of the yield with the multiplicity, with the slope being smaller for larger rapidities. As the isolated photon production is not affected by the fragmentation process, a future experimental investigation of this process in current high energy hadronic colliders is ideal to test the treatment of high multiplicity events using the CGC formalism, previously applied only for the production of hadronic final states.
Comment: 9 pages, 6 figures. Improved version published in European Physical Journal A