Measurement of the production cross-section of $J/\psi$ and $\psi(2$S$)$ mesons in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

TL;DR

This paper reports detailed measurements of the production rates and fractions of $J/$ and $(2S)$ mesons in proton-proton collisions at 13 TeV, providing insights into quarkonium production mechanisms.

Contribution

It presents the first comprehensive differential cross-section measurements for prompt and non-prompt $J/$ and $(2S)$ mesons at 13 TeV with high precision.

Findings

Measured differential cross-sections for $J/$ and $(2S)$ mesons.

Determined non-prompt fractions of $J/$ and $(2S)$ mesons.

Calculated prompt and non-prompt $(2S)$-to-$J/$ production ratios.

Abstract

Measurements of the differential production cross-sections of prompt and non-prompt $J/\psi$ and $\psi(2$S$)$ mesons with transverse momenta between 8 and 360 GeV and rapidity in the range $|y|<2$ are reported. Furthermore, measurements of the non-prompt fractions of $J/\psi$ and $\psi(2$S$)$, and the prompt and non-prompt $\psi(2$S$)$-to-$J/\psi$ production ratios, are presented. The analysis is performed using 140 fb$^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data recorded by the ATLAS detector at the LHC during the years 2015-2018.