Pseudoscalar heavy quarkonium production in heavy ion ultraperipheral collision

TL;DR

This paper calculates the production rates of pseudoscalar heavy quarkonia in heavy ion ultraperipheral collisions using next-to-leading order QCD within the NRQCD framework, providing detailed phenomenological analysis and predictions for future colliders.

Contribution

It presents the first NLO QCD calculations of pseudoscalar heavy quarkonium production in heavy ion UPCs, including cross sections and phenomenological insights.

Findings

Total cross section for η_c at 5.52 TeV is 194 nb.

Cross sections for η_b and B_c are significantly smaller.

Uncertainties from scale and quark mass are analyzed.

Abstract

The inclusive production of pseudoscalar heavy quarkoniua ($\eta_c,~\eta_b$ and $B_c$) via photon-photon fusion in heavy ion ultraperipheral collision (UPC) are calculated to QCD next-to-leading order in the framework of non-relativistic QCD (NRQCD). The total cross section of $\eta_c$ produced in Pb-Pb UPC is 194 $\mathrm{nb}$ and 1275 $\mathrm{nb}$ at nucleon-nucleon c.m. energies $\sqrt{S_{\mathrm{NN}}}=$ 5.52 TeV and 39.4 TeV, respectively. The cross sections for $\eta_b$ and $B_c$ mesons are more than two to three orders of magnitude smaller. We make a detailed phenomenological analysis on the $\eta_c$ production; the uncertainties caused by the renormalization scale and the charm quark mass, the cross sections in other ultraperipheral nucleon-nucleon colliding systems, and the transverse momentum distribution are discussed. At the coming HL-LHC and future FCC, the heavy ion UPC opens another door of the study on the production of heavy quarkonium.