Measurement of the upsilon(1S) production cross-section in pp collisions at root s=7 TeV in ATLAS ATLAS Collaboration
Number of Authors: 3027
2011 (English)In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 705, no 1-2, 9-27 p.Article in journal (Refereed) Published
A measurement of the cross-section for upsilon(1S) -> mu(+)mu(-) production in proton-proton collisions at centre of mass energy of 7 TeV is presented. The cross-section is measured as a function of the upsilon(1S) transverse momentum in two bins of rapidity, vertical bar y(upsilon(1S))vertical bar < 1.2 and 1.2 < vertical bar y(upsilon(1S))vertical bar < 2.4. The measurement requires that both muons have transverse momentum p(T)(mu) > 4 GeV and pseuclorapidity vertical bar eta(mu)vertical bar < 2.5 in order to reduce theoretical uncertainties on the acceptance, which depend on the poorly known polarisation. The results are based on an integrated luminosity of 1.13 pb(-1), collected with the ATLAS detector at the Large Hadron Collider. The cross-section measurement is compared to theoretical predictions: it agrees to within a factor of two with a prediction based on the NRQCD model including colour-singlet and colour-octet matrix elements as implemented in PYTHIA while it disagrees by up to a factor of ten with the next-to-leading order prediction based on the colour-singlet model.
Place, publisher, year, edition, pages
Elsevier, 2011. Vol. 705, no 1-2, 9-27 p.
IdentifiersURN: urn:nbn:se:kth:diva-51362DOI: 10.1016/j.physletb.2011.09.092ISI: 000296937000003ScopusID: 2-s2.0-80054760375OAI: oai:DiVA.org:kth-51362DiVA: diva2:464011
QC 20111212. QC 20160128 Author count: 3027.2011-12-122011-12-122016-01-28Bibliographically approved