Measurement of upsilon production in pp collisions at root s=7 TeV
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Author(s)
Type
Journal Article
Abstract
The production of Υ (1S), Υ (2S) and Υ (3S)
mesons in proton-proton collisions at the centre-of-mass energy
of √s = 7 TeV is studied with the LHCb detector. The
analysis is based on a data sample of 25 pb−1 collected
at the Large Hadron Collider. The Υ mesons are reconstructed
in the decay mode Υ → μ+μ− and the signal yields
are extracted from a fit to the μ+μ− invariant mass distributions.
The differential production cross-sections times
dimuon branching fractions are measured as a function of
the Υ transverse momentum pT and rapidity y, over the
range pT < 15 GeV/c and 2.0 <y< 4.5. The cross-sections
times branching fractions, integrated over these kinematic
ranges, are measured to be
σ
pp → Υ (1S)X
× B
Υ (1S) → μ+μ−
= 2.29 ± 0.01 ± 0.10+0.19
−0.37 nb,
σ
pp → Υ (2S)X
× B
Υ (2S) → μ+μ−
= 0.562 ± 0.007 ± 0.023+0.048
−0.092 nb,
σ
pp → Υ (3S)X
× B
Υ (3S) → μ+μ−
= 0.283 ± 0.005 ± 0.012+0.025
−0.048 nb,
where the first uncertainty is statistical, the second systematic
and the third is due to the unknown polarisation of the
three Υ states.
mesons in proton-proton collisions at the centre-of-mass energy
of √s = 7 TeV is studied with the LHCb detector. The
analysis is based on a data sample of 25 pb−1 collected
at the Large Hadron Collider. The Υ mesons are reconstructed
in the decay mode Υ → μ+μ− and the signal yields
are extracted from a fit to the μ+μ− invariant mass distributions.
The differential production cross-sections times
dimuon branching fractions are measured as a function of
the Υ transverse momentum pT and rapidity y, over the
range pT < 15 GeV/c and 2.0 <y< 4.5. The cross-sections
times branching fractions, integrated over these kinematic
ranges, are measured to be
σ
pp → Υ (1S)X
× B
Υ (1S) → μ+μ−
= 2.29 ± 0.01 ± 0.10+0.19
−0.37 nb,
σ
pp → Υ (2S)X
× B
Υ (2S) → μ+μ−
= 0.562 ± 0.007 ± 0.023+0.048
−0.092 nb,
σ
pp → Υ (3S)X
× B
Υ (3S) → μ+μ−
= 0.283 ± 0.005 ± 0.012+0.025
−0.048 nb,
where the first uncertainty is statistical, the second systematic
and the third is due to the unknown polarisation of the
three Υ states.
Date Issued
2012-06-01
Date Acceptance
2012-04-20
Citation
European Physical Journal C, 2012, 72 (6)
ISSN
1434-6052
Publisher
Springer Verlag (Germany): SCOAP3
Journal / Book Title
European Physical Journal C
Volume
72
Issue
6
Copyright Statement
© CERN for the benefit of the LHCb collaboration 2012. This article is published with open access at Springerlink.com
License URL
Subjects
Science & Technology
Physical Sciences
Physics, Particles & Fields
Physics
PHYSICS, PARTICLES & FIELDS
OCTET QUARKONIA PRODUCTION
HADRONIC COLLISIONS
J-PSI
DECAY
Publication Status
Published
Article Number
2025