摘要: Differential cross sections as a function of transverse momentum pT are presented for the production of ϒ(nS) (n = 1, 2, 3) states decaying into a pair of muons. Data corresponding to an integrated luminosity of 4.9fb−1 in pp collisions at s=7TeV were collected with the CMS detector at the LHC. The analysis selects events with dimuon rapidity |y|<1.2 and dimuon transverse momentum in the range 10<pT<100GeV. The measurements show a transition from an exponential to a power-law behavior at pT≈20GeV for the three ϒ states. Above that transition, the ϒ(3S) spectrum is significantly harder than that of the ϒ(1S). The ratios of the ϒ(3S) and ϒ(2S) differential cross sections to the ϒ(1S) cross section show a rise as pT increases at low pT, then become flatter at higher pT. 出版者: Elsevier 出版日期: 2015-10-07 出處: Physics letters. B, 2015-10, Vol.749 (C), p.14-34 資源來源: Elsevier ScienceDirect Journals 識別號: ISSN: 0370-2693 識別號: EISSN: 1873-2445 識別號: DOI: 10.1016/j.physletb.2015.07.037