Relativistic corrections to double charmonium production in high energy proton-proton interaction

TL;DR

This paper calculates relativistic corrections to double J/psi production in high-energy proton-proton collisions, showing these effects significantly reduce the predicted cross section, but still below experimental measurements.

Contribution

It introduces a comprehensive relativistic correction framework for double charmonium production in proton-proton collisions at LHC energies, combining perturbative QCD and a relativistic quark model.

Findings

Relativistic effects decrease the cross section by more than two times.

The corrected cross section remains below LHCb experimental data.

Relativistic corrections are essential for accurate theoretical predictions.

Abstract

On the basis of pertubative QCD and the relativistic quark model we calculate relativistic corrections to the process of pair $J/\psi$ production in proton-proton collisions at LHC energy $\sqrt S=7$ TeV. Relativistic terms in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave functions to the reference frame of moving $J/\psi$ mesons are taken into account. For the gluon and quark propagators entering the amplitude we use a truncated expansion in relative quark momenta up to the second order. Relativistic corrections to the quark bound state wave functions are considered by means of the Breit-like potential. It turns out that the examined effects decrease initial nonrelativistic cross section more than two times. The final result lies below the experimental value measured by LHCb.