Measurement of the η[subscript c](1S) production cross-section in proton–proton collisions via the decay η[subscript c](1S) → p[bar over p]
Name
Aaij-2015-Measurement of the (.pdf
Size
1023.48 KB
Format
Adobe PDF
Checksum (MD5)
701e5a38d9b6735f44ca65b3183de57d
Author(s) • •
Counts, Ian Thomas Hunt
Williams, Michael
Ilten, Philip J
Date Issued
July 2015
Journal
The European Physical Journal C
Publisher
Springer-Verlag
Citation
Aaij, R., C. Abellán Beteta, B. Adeva, M. Adinolfi, A. Affolder, Z. Ajaltouni, S. Akar, et al. “Measurement of the η[subscript c](1S) Production Cross-Section in Proton–proton Collisions via the Decay η[subscript c](1S) → p[bar over p].” The European Physical Journal C 75, no. 7 (July 2015). © 2015 CERN for the benefit of the LHCb collaboration
Version
Final published version
Abstract
The production of the η[subscript c](1S) state in proton-proton collisions is probed via its decay to the p[bar over p] final state with the LHCb detector, in the rapidity range 2.0 < y < 4.5 and in the meson transverse-momentum range p[subscript T] > 6.5 GeV/c. The cross-section for prompt production of η[subscript c](1S) mesons relative to the prompt J/ψ cross-section is measured, for the first time, to be [superscript σ]η[subscript c](1S)/σ[subscript J/ψ] = 1.74 ± 0.29 ± 0.28 ± 0.18[subscript B] at a centre-of-mass energy √s = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb[superscript −1], and [superscript σ]η[subscript c](1S)/σ[subscript J/ψ] = 1.60 ± 0.29 ± 0.25 ± 0.17[subscript B] at √s = 8 TeV using 2.0 fb[superscript −1]. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the η[subscript c](1S) and J/ψ decays to the p[bar over p] final state. In addition, the inclusive branching fraction of b-hadron decays into η[subscript c](1S) mesons is measured, for the first time, to be B(b → η[subscript c]X) = (4.88 ± 0.64 ± 0.29 ± 0.67[subscript B]) × 10[superscript −3], where the third uncertainty includes also the uncertainty on the J/ψ inclusive branching fraction from b-hadron decays. The difference between the J/ψ and η[subscript c](1S) meson masses is determined to be 114.7 ± 1.5 ± 0.1 MeV/c[superscript 2].
MIT Department
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1140/epjc/s10052-015-3502-x