The CMS collaboration; Sirunyan, A. M.; Eerola, P.; Kirschenmann, H.; Pekkanen, J.; Voutilainen, M.; Havukainen, J.; Heikkilä, J. K.; Järvinen, T.; Karimäki, V.; Kinnunen, R.; Lampén, T.; Lassila-Perini, K.; Laurila, S.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Siikonen, H.; Tuominen, E.; Tuominiemi, J.; Tuuva, T.
(2018)
The differential yields of charged particles having pseudorapidity within vertical bar eta vertical bar < 1 are measured using xenon-xenon (XeXe) collisions at root S-NN = 5.44 TeV. The data, corresponding to an integrated luminosity of 3.42 mu b(-1), were collected in 2017 by the CMS experiment at the LHC. The yields are reported as functions of collision centrality and transverse momentum, pT, from 0.5 to 100 GeV. A previously reported pT spectrum from proton-proton collisions at root S = 5.02 TeV is used for comparison after correcting for the difference in center-of-mass energy. The nuclear modification factors using this reference, R-AA*, are constructed and compared to previous measurements and theoretical predictions. In head-on collisions, the R-AA* has a value of 0.17 in the pT range of 6-8 GeV, but increases to approximately 0.7 at 100 GeV. Above approximate to 6 GeV, the XeXe data show a notably smaller suppression than previous results for lead-lead (PbPb) collisions at root S-NN = 5.02 TeV when compared at the same centrality (i.e., the same fraction of total cross section). However, the XeXe suppression is slightly greater than that for PbPb in events having a similar number of participating nucleons.