In:
Journal of High Energy Physics, Springer Science and Business Media LLC, Vol. 2012, No. 11 ( 2012-11)
Abstract:
The ALICE experiment at the LHC has studied J/ ψ production at mid-rapidity in pp collisions at $ \sqrt{s}=7 $ TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L int = 5 . 6 nb −1 . The fraction of J/ ψ from the decay of long-lived beauty hadrons was determined for J/ ψ candidates with transverse momentum p t 〉 1 . 3 GeV/ c and rapidity | y | 〈 0 . 9. The cross section for prompt J/ ψ mesons, i.e. directly produced J/ ψ and prompt decays of heavier charmonium states such as the ψ (2S) and χ c resonances, is σ prompt J/ ψ ( p t 〉 1 . 3 GeV /c, | y | 〈 0 . 9) = 8 . 3 ± 0 . 8 (stat . ) ± 1 . 1 (syst . ) $ _{-1.4}^{+1.5 } $ (syst . pol . ) μ b. The cross section for the production of b-hadrons decaying to J/ ψ with p t 〉 1 . 3 GeV/ c and | y | 〈 0 . 9 is $ {\sigma_{{{J \left/ {{\psi \leftarrow {{\mathrm{h}}_{\mathrm{B}}}}} \right.}}}} $ ( p t 〉 1.3 GeV/ c , | y | 〈 0.9) = 1.46 ± 0.38 (stat.) $ _{-0.32}^{+0.26 } $ (syst.) μ b. The results are compared to QCD model predictions. The shape of the p t and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the $ \mathrm{b}\overline{\mathrm{b}} $ pair total cross section and d σ/ d y at mid-rapidity.
Type of Medium:
Online Resource
ISSN:
1029-8479
DOI:
10.1007/JHEP11(2012)065
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2012
detail.hit.zdb_id:
2027350-2
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