Multiplicity dependence of prompt and non-prompt J/ψ production at midrapidity in pp collisions at TeV

A bstract The yields of prompt and non-prompt J/ ψ and the fraction of non-prompt J/ ψ are measured at midrapidity (| y | < 0.9) via the dielectron decay channel as a function of the midrapidity charged-particle multiplicity (| η | < 0.9) in pp collisions at $$\sqrt{s}=13$$ TeV. The J/ ψ yields and the multiplicity are normalized by their average value in inelastic collisions. The multiplicity-dependent yield ratio between prompt J/ ψ and D 0 is reported. The multiplicity is further divided into three azimuthal regions with respect to the J/ ψ momentum: toward the J/ ψ emission direction, transverse, or opposite to it. A stronger-than-linear increase of the self-normalized yields is observed for both prompt and non-prompt J/ ψ production, with similar trends. This behaviour is also observed in the toward region, while a weaker increase is observed in the transverse and away regions.