Determinação da distribuição de glúons do próton na fotoprodução de mésons vetoriais no Grande Colisor de Hádrons

Abstract

One of the main open questions in the Standard Model of the Particle Physics is the structure of protons and neutrons in the high energy regime, which is described by the strong interactions theory - the Quantum Chromodynamics (QCD). Data from the HERA collider allowed us to study in detail the electron-proton interaction at high energies, allowing satisfactorily constrain the content of quarks inside the proton. However, the uncertainty in the content of gluons inside the proton is still large. In this work we study the photoproduction of heavy vector mesons (J/ψ and Υ) in electron-proton collisions and in hadron - hadron interactions at the Large Hadron Colider, considering various existing parameterizations in the literature for the gluon distribution. As the γp cross section and the distribution of rapidity for the pp process are proportional to the square of the gluon distribution function of the proton, the differences between existing parameterizations in the literature are amplified. Our results demonstrate that this process can be used to determine the behavior of the gluon distribution.