# Measurement of $\Upsilon$ production in $pp$ collisions at $\sqrt{s}$= 13 TeV

[to restricted-access page]

## Abstract

The production cross-sections of $\Upsilon(1S)$, $\Upsilon(2S)$ and $\Upsilon(3S)$ mesons in proton-proton collisions at $\sqrt{s}$= 13 TeV are measured with a data sample corresponding to an integrated luminosity of $277 \pm 11$ $\rm pb^{-1}$ recorded by the LHCb experiment in 2015. The $\Upsilon$ mesons are reconstructed in the decay mode $\Upsilon\to\mu^{+}\mu^{-}$. The differential production cross-sections times the dimuon branching fractions are measured as a function of the $\Upsilon$ transverse momentum, $p_{\rm T}$, and rapidity, $y$, over the range $0 < p_{\rm T}< 30$ GeV/c and $2.0 < y < 4.5$. The ratios of the cross-sections with respect to the LHCb measurement at $\sqrt{s}$= 8 TeV are also determined. The measurements are compared with theoretical predictions based on NRQCD.

 Dimuon invariant mass distribution of $\Upsilon$ candidates with $0< p_{\rm T} <30 {\mathrm{ Ge V /}c}$ and $2.0 ## Tables and captions  Summary of the relative systematic uncertainties (in$\%$) on the$\Upsilon$production cross-sections times dimuon branching fractions. Some of the uncertainties are correlated between intervals. For the trigger, track reconstruction and muon identification efficiencies, the uncertainties are larger in the high rapidity region. The uncertainties on the tracking efficiency account for both the limited size of the control samples (first parenthesis) and the impact of different multiplicity between data and simulation on each track (second parenthesis). Table_1.pdf [35 KiB] HiDef png [99 KiB] Thumbnail [45 KiB] tex code Double-differential cross-sections times dimuon branching fraction in different bins of$p_{\rm T}$and$y$for$\Upsilon{(1S)} $(in$\rm pb$). The first uncertainty is statistical and the second is systematic. Table_2.pdf [35 KiB] HiDef png [269 KiB] Thumbnail [132 KiB] tex code Double-differential cross-sections times dimuon branching fraction in different bins of$p_{\rm T}$and$y$for$\Upsilon{(2S)} $(in$\rm pb$). The first uncertainty is statistical and the second is systematic. Table_3.pdf [35 KiB] HiDef png [279 KiB] Thumbnail [122 KiB] tex code Double-differential cross-sections times dimuon branching fraction in different bins of$p_{\rm T}$and$y$for$\Upsilon{(3S)} $(in$\rm pb$). The first uncertainty is statistical and the second is systematic. Table_4.pdf [35 KiB] HiDef png [273 KiB] Thumbnail [125 KiB] tex code The cross-section ratios between 13 TeV and 8 TeV in different bins of$p_{\rm T}$and$y$for$\Upsilon{(1S)}$. Table_5.pdf [34 KiB] HiDef png [257 KiB] Thumbnail [126 KiB] tex code The cross-section ratios between 13 TeV and 8 TeV in different bins of$p_{\rm T}$and$y$for$\Upsilon{(2S)}$. Table_6.pdf [34 KiB] HiDef png [253 KiB] Thumbnail [125 KiB] tex code The cross-section ratios between 13 TeV and 8 TeV in different bins of$p_{\rm T}$and$y$for$\Upsilon{(3S)}\$ . Table_7.pdf [34 KiB] HiDef png [254 KiB] Thumbnail [126 KiB] tex code

Created on 07 August 2020.