Measurement of the ratio of prompt ${\chi }_c$ to $J/\psi$ production in $pp$ collisions at $\sqrt{s}=7$ TeV

LHCb Collaboration, R. Aaij, C. Abellan Beteta +591

The prompt production of charmonium ${\chi }_c$ and $J/\psi$ states is studied in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=7$ TeV at the Large Hadron Collider. The…