Pair production of heavy quarkonia in the color evaporation model

TL;DR

This paper investigates the pair production of heavy quarkonia using the improved color evaporation model combined with the parton Reggeization approach, highlighting the roles of single and double parton scattering mechanisms.

Contribution

It introduces a novel combination of the color evaporation model with the parton Reggeization approach for heavy quarkonia pair production analysis.

Findings

Quantitative comparison of single and double parton scattering contributions.

Implementation of the Monte-Carlo generator KaTie for numerical calculations.

Insights into high-energy factorization effects in heavy quarkonia production.

Abstract

In the article, we study pair production of heavy quarkonia $(J/\psi J/\psi, \Upsilon\Upsilon, \Upsilon J/\psi)$ in the improved color evaporation model via the parton Reggeization approach. The last one is based on high-energy factorization of hard processes in multi-Regge kinematics, the Kimber-Martin-Ryskin-Watt model for unintegrated parton distribution functions, and the Lipatov effective field theory of Reggezied gluons and quarks. We compare contributions from the single and double parton scattering mechanisms in the pair production of heavy quarkonia. The numerical calculations are performed with the Monte-Carlo event generator KaTie.