Measurement of upsilon production in 7 TeV pp collisions at ATLAS
Number of Authors: 2898
2013 (English)In: Physical Review D, ISSN 1550-7998, Vol. 87, no 5, 052004- p.Article in journal (Refereed) Published
Using 1.8 fb(-1) of pp collisions at a center- of- mass energy of 7 TeV recorded by the ATLAS detector at the Large Hadron Collider, we present measurements of the production cross sections of Upsilon(1S,2S,3S) mesons. Upsilon mesons are reconstructed using the dimuon decay mode. Total production cross sections for p(T) < 70 GeV and in the rapidity interval vertical bar y(Upsilon)vertical bar < 2. 25 are measured to be, 8.01 +/- 0.02 +/- 0.36 +/- 0.31 nb, 2.05 +/- 0.01 +/- 0.12 +/- 0.08 nb, and 0.92 +/- 0.01 +/- 0.07 +/- 0.04 nb, respectively, with uncertainties separated into statistical, systematic, and luminosity measurement effects. In addition, differential cross section times dimuon branching fractions for Upsilon(1S), Upsilon(2S), and Upsilon(3S) as a function of Upsilon transverse momentum pT and rapidity are presented. These cross sections are obtained assuming unpolarized production. If the production polarization is fully transverse or longitudinal with no azimuthal dependence in the helicity frame, the cross section may vary by approximately +/- 20%. If a nontrivial azimuthal dependence is considered, integrated cross sections may be significantly enhanced by a factor of 2 or more. We compare our results to several theoretical models of Upsilon meson production, finding that none provide an accurate description of our data over the full range of Upsilon transverse momenta accessible with this data set.
Place, publisher, year, edition, pages
2013. Vol. 87, no 5, 052004- p.
Octet Quarkonia Production, Prompt J/Psi Production, Root-S=7 Tev, Heavy Quarkonium, J-Psi, Charmonium Production, Hadronic Collisions, Polarization, Gluons, Qcd
IdentifiersURN: urn:nbn:se:kth:diva-120449DOI: 10.1103/PhysRevD.87.052004ISI: 000315737000003ScopusID: 2-s2.0-84875029801OAI: oai:DiVA.org:kth-120449DiVA: diva2:614846
FunderSwedish Research Council
QC 20130408. Author count: 28982013-04-082013-04-082013-04-08Bibliographically approved