Measurement of $J/\psi$ photoproduction in UPC of PbPb at 5 TeV

A first look at $J/\psi$ photoproduction in ultra-peripheral PbPb collisions at center-of-mass energy $\sqrt{s_{NN}} = 5\, \mathrm{TeV}$ with the LHCb experiment is presented. The measurement is based on a low multiplicity data sample of $J/\psi$ mesons, decaying through the dimuon channel. An analysis of signal contamination as well as a method of two stage fit to obtain yield of coherent $J/\psi$ is described.