QED contribution to the production of J/\psi+c\bar{c}+X at the Tevatron and LHC

TL;DR

This paper calculates the QED contribution to J/ production at Tevatron and LHC, showing it enhances the p_{t} distribution and affects polarization, providing new insights into collider signals.

Contribution

It introduces the first calculation of _s^2 order QED effects on J/ production, including interference with QCD, in a non-relativistic QCD framework.

Findings

QED contribution increases p_{t} distribution by factors of 1.5 and 1.9 at Tevatron and LHC.

J/ polarization shifts from unpolarized to transverse with increasing p_{t}.

Associated J/ production with charm quarks could be experimentally measurable.

Abstract

We calculate \alpha^{2}\alpha_{s}^{2} order QED contribution to J/\psi production in pp(\bar{p})\to J/\psi+c\bar{c} color-singlet process at the Tevatron and LHC in the framework of non-relativistic QCD. The contribution of the interference between the \alpha^{2}\alpha_{s}^{2} QED and \alpha_{s}^{4} QCD is also taken into account. The J/\psi production associated with a charm quark pair could be a measurable signal at hadron collider experiment. Our calculations show that by including the QED contribution, the p_{t} distribution is enhanced by a factor of 1.5 (1.9) at the Tevatron (LHC) at p_{t}=50 (100) GeV. In addition, the polarization of J/\psi turns from unpolarized in all region to increasingly transverse when p_{t} becomes larger.