Exclusive Photo-production of J/Ψ and Ψ(2s) as a tool to explore the transition to high and saturated gluon densities at the LHC.

Authors

  • Marco Antonio Alcazar Peredo Universidad de las Américas Puebla
  • Martin Hentschinski Universidad de las Américas Puebla

DOI:

https://doi.org/10.31349/SuplRevMexFis.4.021121

Keywords:

Quantum chromodynamics; deep inelastic scattering; large hadron collider; forward physics; ultra-peripheral collisions; gluon distribution

Abstract

We study the energy dependence of the cross-section for exclusive photo-production of vector mesons J/Ψ and Ψ(2s) and search for signs for the onset of non-linear QCD dynamics in this observable. Our study is based on two dipole models: the Golec-Biernat, Wuesthoff Model (GBW) and the Bartels, Golec-Biernat, Kowal- ski Model (BGK). We find that differences between linear and non-linear implementations of these models are relatively small in the kinematic region probed by both HERA and LHC experiments if the energy dependence of the photo-production cross-section is being considered. We however find that the ratio of both cross-sections grows with energy in the presence of non-linear effects, while it remains approximately constant in the linearized case. The ratio of photo-production cross-sections might therefore provide a suitable tool to characterize the size of non-linear QCD effects at current collider energies.

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Published

2023-09-18

How to Cite

1.
Alcazar Peredo MA, Hentschinski M. Exclusive Photo-production of J/Ψ and Ψ(2s) as a tool to explore the transition to high and saturated gluon densities at the LHC. Supl. Rev. Mex. Fis. [Internet]. 2023 Sep. 18 [cited 2024 Jun. 18];4(2):021121 1-4. Available from: https://rmf.smf.mx/ojs/index.php/rmf-s/article/view/7151