Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Choudhury, R. K.; Dutta, D.; Kailas, S.; Kumar, V.; Mohanty, A. K.; Pant, L. M.; Shukla, P.; and others
Source
Journal of High Energy Physics, 2011. Vol. 8: pp. 10.1007/JHEP08(2011)086
ABSTRACT
The charged particle transverse momentum (pT) spectra are presented for pp collisions at √s = 0.9 and 7TeV. The data samples were collected with the CMS detector at the LHC and correspond to integrated luminosities of 231 μb-1 and 2.96 pb-1, respectively. Calorimeter-based high-transverse-energy triggers are employed to enhance the statistical reach of the high-pT measurements. The results are compared with leading and next-to-leading order QCD and with an empirical scaling of measurements at different collision energies using the scaling variable xT ≡ 2pT/√s over the pT range up to 200 GeV/c. Using a combination of xT scaling and direct interpolation at fixed pT, a reference transverse momentum spectrum at √s = 2.76TeV is constructed, which can be used for studying high-pT particle suppression in the dense QCD medium produced in heavy-ion collisions at that centre-of-mass energy.