Measurement of $J/\psi$ production cross-section in pp collisions at $\sqrt{s_{NN}} = 5 \mathrm{TeV}$

The $J/\psi$ production cross-sections of $J/\psi$ mesons at $\sqrt{s_{\mathrm{NN}}}$ = 5 $\mathrm{TeV}$ are studied using \lhcb detector, correponding to an integrated lumionisity of 7.97 $\pm$ 0.30 $\mathrm{pb^{-1}}$. The production cross-sections of prompt $J/\psi$ and $J/\psi$ mesons from b-hadron decays are measured separately as a function of transverse momentum and rapidity. The measurement is performed in the range of $0 < p_{\mathrm{T}} < 14 ~\mathrm{GeV}/c$ and $2 < y < 4.5$. The integrated production cross-sections are (preliminary) $8.39 \pm 0.01(\mathrm{stat}) \pm 0.46(\mathrm{syst}) \mathrm{\mu b}$ for prompt $J/\psi$ and $0.941 \pm 0.001(\mathrm{stat}) \pm 0.047(\mathrm{syst}) \mathrm{\mu b}$ for $J/\psi$ from $b$.