Measurement of exclusive Y photoproduction in pPb collisions at $\sqrt{s_{_\mathrm{NN}}} = 5.02~\mathrm{TeV}$

A measurement of exclusive photoproduction of Y(1S), Y(2S) and Y(3S) mesons, in their $\mu^+\mu^-$ decay modes, in ultraperipheral pPb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV is presented. The measurement is based on data collected by the CMS experiment corresponding to an integrated luminosity of $32.6~\mathrm{nb}^{-1}$. The Y(1S) photoproduction cross section is measured, over the rapidity range $|y|<2.2$, as a function of the photon-proton center-of-mass energy, $W_{\gamma\mathrm{p}}$, in the range $91 < W_{\gamma\mathrm{p}} < 826~\mathrm{GeV}$. The differential cross section $\mathrm{d}\sigma/\mathrm{d}|t|$, where $|t| \approx p_\mathrm{T}^2$ is the squared transverse momentum of the Y(nS) mesons is measured in the range $0.01<|t|<1~\mathrm{GeV}^2$. The results are compared to other measurements and to theoretical predictions.