Measurement of the ratio of prompt ${\chi }_c$ to $J/\psi$ production in $pp$ collisions at $\sqrt{s}=7$ TeV

Abstract

The prompt production of charmonium ${\chi }_c$ and $J/\psi$ states is studied in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=7$ TeV at the Large Hadron Collider. The ${\chi }_c$ and $J/\psi$ mesons are identified through their decays ${\chi }_c\to J/\psi \gamma$ and $J/\psi \to {\mu }^{+}{\mu }^{-}$ using 36 pb${}^{-1}$ of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for ${\chi }_c$ and $J/\psi$, $\sigma ({\chi }_c\to J/\psi \gamma )/\sigma (J/\psi )$, is determined as a function of the $J/\psi$ transverse momentum in the range $2<p_{\mathrm{T}}^{J/\psi }<15$ GeV/$c$. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low $p_{\mathrm{T}}^{J/\psi }$ region.

Published version

References in corpus (3)

• PYTHIA 6.4 Physics and Manual
• QCD radiative corrections to ${\chi }_{cJ}$ production at hadron colliders
• Production of the Charmonium States chic_1 and chic_2 in Proton Nucleus Interactions at sqrt{s} = 41.6 GeV

Cited by in corpus (19)

• Polarization for Prompt J/psi, psi(2s) production at the Tevatron and LHC
• ${\eta }_c$ production at the LHC challenges nonrelativistic-QCD factorization
• Impact of ${\eta }_c$ hadroproduction data on charmonium production and polarization within NRQCD framework
• An experimental review of open heavy flavor and quarkonium production at RHIC
• Studies of J/$\psi$ production at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review
• Production of exotic hadrons in $pp$ and nuclear collisions
• Measurement of the fraction of \Y1S originating from \chib1P decays in $pp$ collisions at $\sqrt{s} = 7\tev$
• Study of $\eta -{\eta }^{\prime }$ mixing from measurement of $B_{(s)}^0\to J/\psi {\eta }^{(\prime )}$~decay rates
• Prospects for quarkonium studies at the high-luminosity LHC
• h_c Production at Hadron Colliders
• Recombination of $B_c$ mesons in ultra-relativistic heavy-ion collisions
• Yields and polarizations of prompt $\jpsi$ and $\psits$ production in hadronic collisions
• Fraction of ${\chi }_c$ decays in prompt $J/\psi$ production measured in pPb collisions at $\sqrt{s_{NN}}=8.16$ TeV
• Inclusive diffractive heavy quarkonium photoproduction in pp, pA and AA collisions
• Prospects for studies of $D^{\ast 0}\to {\mu }^{+}{\mu }^{-}$ and $B_{(s)}^{\ast 0}\to {\mu }^{+}{\mu }^{-}$ decays
• Study of $B_c(1P{)}^{+}$ states in the $B_c^{+}\gamma$ mass spectrum
• Systematic study of Charmonium production in pp collisions at the LHC energies
• Absorption of 1$P$-wave heavy charmonium ${\chi }_{c1}(1P)$ in nuclei