Measurement of associated $J/\psi$-$\psi (2S)$ production cross-section in $pp$ collisions at $\sqrt{s}=13$ TeV

Abstract

The cross-section of associated $J/\psi$-$\psi (2S)$ production in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=13$ TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fb${}^{-1}$, collected by the LHCb experiment. The measurement is performed for both $J/\psi$ and $\psi (2S)$ mesons having transverse momentum $p_{\text{T}}<14$ GeV/$c$ and rapidity $2.0<y<4.5$, assuming negligible polarisation of the $J/\psi$ and $\psi (2S)$ mesons. The production cross-section is measured to be $4.5\pm 0.7\pm 0.3$ nb, where the first uncertainty is statistical and the second systematic. The differential cross-sections are measured as functions of several kinematic variables of the $J/\psi$-$\psi (2S)$ candidates. The results are combined with a measurement of $J/\psi$-$J/\psi$ production, giving a cross-section ratio between $J/\psi$-$\psi (2S)$ and $J/\psi$-$J/\psi$ production of $0.274\pm 0.044\pm 0.008$, where the first uncertainty is statistical and the second systematic.

All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-023.html (LHCb public pages)

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Cited by in corpus (1)

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