Charm fragmentation and associated $J/\psi + Z/W^\pm$ production at the LHC

TL;DR

This paper investigates the production of $J/ar{psi}$ mesons with electroweak bosons at the LHC, introducing new partonic subprocesses involving charm and strange quark excitation and fragmentation, which improve agreement with experimental data.

Contribution

It introduces and analyzes new partonic subprocesses involving charm and strange quark excitation and fragmentation in associated $J/ar{psi}$ and electroweak boson production at the LHC.

Findings

New subprocesses significantly reduce the gap between theory and experiment.

Charmed and strange quark excitation mechanisms are important for accurate predictions.

Multiple quark and gluon radiation effects are also considered.

Abstract

We consider the production of electroweak $Z$ or $W^\pm$ bosons associated with $J/\psi$ mesons at the LHC conditions. Our attention is focused on new partonic subprocesses which yet have never been considered in the literature, namely, the charmed or strange quark excitation subprocesses followed by the charmed quark fragmentation $c\to J/\psi+c$. Additionally we take into account the effects of multiple quark and gluon radiation in the initial and final states. We find that the contributions from the new mechanisms are important and significantly reduce the gap between the theoretical and experimental results on the $J/\psi + Z$ and $J/\psi + W^\pm$ production cross sections.