# Comments on "Study of $J/\psi$ production in jets"

## TL;DR

This paper analyzes LHCb measurements of $J/$ production in jets using fragmentation functions, explaining discrepancies with theory by considering evolution effects and double parton scattering contributions.

## Contribution

It introduces an improved analysis incorporating fragmentation function evolution and double parton scattering to better match experimental data.

## Key findings

- Discrepancies in $z(J/\psi)$ distributions explained by evolution effects.
- Double parton scattering significantly contributes to $J/\psi$ production.
- Enhanced theoretical understanding of $J/\psi$ production mechanisms.

## Abstract

Recent LHCb measurements of the $J/\psi$ meson production in jets is analyzed using fragmentation jet function formalism. It is shown that disagreement with theoretical predictions for distribution over the fraction of $J/\psi$ transverse momentum $z(J/\psi)$ in the cases of prompt production can be explained if one takes into account evolution of the fragmentation function and contributions from double parton scattering mechanism.