Charged-particle nuclear modification factors in XeXe collisions at $\sqrt{s_{\mathrm{NN}}}=5.44~\mathrm{TeV}$

The differential yields of charged particles having pseudorapidity within $|\eta|<1$ are measured using 3.42 $\mu\mathrm{b}^{-1}$ of XeXe collisions at $\sqrt{s_{\mathrm{NN}}}=5.44~\mathrm{TeV}$ 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$~\mathrm{GeV}$. A previously reported $p_{\mathrm{T}}$ spectrum from pp collisions at $\sqrt{s}=5.02~\mathrm{TeV}$ is extrapolated in center-of-mass energy to form a suitable reference for comparison. The nuclear modification factors, $R^{*}_{\mathrm{AA}}$, are constructed with this extrapolated reference and compared to previous measurements and theoretical predictions. In head-on collisions the $R^{*}_{\mathrm{AA}}$ is suppressed by a factor of six in the $p_{\mathrm{T}}$ range of 6--9$~\mathrm{GeV}$ but increases to approximately 0.7 at $100~\mathrm{GeV}$. A ratio between the XeXe spectra and previously reported spectra from PbPb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02~\mathrm{TeV}$ indicates a notably smaller suppression of charged-particle production for the same centrality selection and $p_{\mathrm{T}}>6~\mathrm{GeV}$. However, the suppression in XeXe events is slightly greater than in PbPb collisions when comparing selections having a similar number of participating nucleons.