Diffractive semi-hard production of a $J/\psi$ or a $\Upsilon$ from single-parton fragmentation plus a jet in hybrid factorization

TL;DR

This paper studies the production of heavy quarkonium with a jet in high-energy collisions using hybrid factorization, aiming to test QCD mechanisms and the transition from pair production to single-parton fragmentation.

Contribution

It introduces a hybrid high-energy and collinear factorization approach with BFKL resummation for quarkonium plus jet production, providing new predictions for differential distributions.

Findings

Predictions for rapidity and azimuthal distributions

Analysis of high-energy series stability under higher-order corrections

Insights into quarkonium production mechanisms at high energies

Abstract

We investigate the inclusive hadroproduction of a heavy quarkonium ($J/\psi$ or $\Upsilon$), in association with a light-flavored jet, as a testing ground for the semi-hard regime of QCD. Our theoretical setup is the hybrid high-energy and collinear factorization, where the standard collinear approach is supplemented by the $t$-channel resummation of leading and next-to-leading energy logarithms \`a la BFKL. We present predictions for rapidity and azimuthal-angle differential distributions, hunting for stabilizing effects of the high-energy series under higher-order corrections. Our reaction represents an additional channel to test the production mechanisms of quarkonia at high energies and large transverse momenta and to possibly shed light on the transition region from heavy-quark pair production to single-parton fragmentation of $J/\psi$ and $\Upsilon$ states.