Measurement of the η c (1S) production cross-section in p p collisions at √s = 13 TeV
Name
Aaij2020_Article_MeasurementOfTheEtaC1SΗc1SProd.pdf
Description
Published version
Size
1.5 MB
Format
Unknown
Checksum (MD5)
37dc3b7d4f9f3095c8da8f400bebfb09
Author(s)
The LHCb Collaboration
Boettcher, Thomas Julian
Craik, Daniel C
Weisser, Constantin
Williams, Michael
Date Issued
2020
Journal
The European Physical Journal C - Particles and Fields
Publisher
Springer Science and Business Media LLC
Version
Final published version
Abstract
Using a data sample corresponding to an integrated luminosity of 2.0 fb−1 , collected by the LHCb experiment, the production of the ηc(1S) state in proton–proton collisions at a centre-of-mass energy of √s = 13 TeV is studied in the rapidity range 2.0 < y < 4.5 and in the transverse momentum range 6.5 < pT < 14.0 GeV. The cross-section for prompt production of ηc(1S) mesons relative to that of the J/ψ meson is measured using the p p decay mode and is found to be σηc (1S) /σJ/ψ = 1.69 ± 0.15 ± 0.10 ± 0.18. The quoted uncertainties are, in order, statistical, systematic and due to uncertainties on the branching fractions of the J/ψ → p p and ηc → p p decays. The prompt ηc(1S) production cross-section is determined to be σηc (1S) = 1.26 ± 0.11 ± 0.08 ± 0.14 μb, where the last uncertainty includes that on the J/ψ meson cross-section. The ratio of the branching fractions of b-hadron decays to the ηc(1S) and J/ψ states is measured to be Bb→ηc X /Bb→J/ψ X = 0.48 ± 0.03 ± 0.03 ± 0.05, where the last uncertainty is due to those on the branching fractions of the J/ψ → p p and ηc → p p decays. The difference between the J/ψ and ηc(1S) masses is also determined to be 113.0 ± 0.7 ± 0.1 MeV, which is the most precise single measurement of this quantity to date.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
10.1140/EPJC/S10052-020-7733-0
