The differential yields of charged particles having pseudorapidity within $|\eta|<$ 1 are measured using xenon-xenon (XeXe) collisions at $\sqrt{s_\mathrm{NN}}$ = 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, $p_\mathrm{T}$, from 0.5 to 100 GeV. A previously reported $p_\mathrm{T}$ spectrum from proton-proton collisions at $\sqrt{s}$ = 5.02 TeV is used for comparison after correcting for the difference in center-of-mass energy. The nuclear modification factors using this reference, $R_\mathrm{AA}^*$, are constructed and compared to previous measurements and theoretical predictions. In head-on collisions, the $R_\mathrm{AA}^*$ has a value of 0.17 in the $p_\mathrm{T}$ range of 6-8 GeV, but increases to approximately 0.7 at 100 GeV. Above $\approx$ 6 GeV, the XeXe data show a notably smaller suppression than previous results for lead-lead (PbPb) collisions at $\sqrt{s_\mathrm{NN}}$ = 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.
The per-event differential invariant yield of charged particles having |eta|<1 in XeXe collisions at sqrt(s_NN)=5.44 TeV. The first systematic uncertainty describes uncertainties that are not fully correlated across points, while the second systematic uncertainty is a normalization uncertainty that is fully correlated across all points. Bins where no data point has been reported are denoted as 'empty'.
The per-event differential invariant yield of charged particles having |eta|<1 in pp collisions at sqrt(s)=5.44 TeV, after extrpolation from 5.02 TeV data. The first systematic uncertainty describes uncertainties that are not fully correlated across points, while the second systematic uncertainty is a normalization uncertainty that is fully correlated across all points. The data is measured and extrapolated as a differential cross section, and transformed into a differential yield using an inelastic cross-section of 70 mb.
The nuclear modification factor of charged particles having |eta|<1 in XeXe collisions at sqrt(s_NN)=5.44 TeV. The first systematic uncertainty describes uncertainties that are not fully correlated across points, while the second systematic uncertainty is a normalization uncertainty that is fully correlated across all points. Bins where no data point has been reported are denoted as 'empty'.
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