Transverse momentum and multiplicity dependence of varLambda _{c}^{+}/D^{0} ratio in pp collisions at sqrt{s}=13 TeV

Abstract

We apply an equal-velocity quark combination model to study the varLambda _{c}^{+}/D^{0} ratio in the range p_{T}lesssim 10 GeV/c in pp collisions at sqrt{s}=13 TeV. We decompose the ratio into four parts which are related to quark numbers, light-flavor quark p_{T} spectrum, charm quark p_{T} spectrum, momentum correlation between light and charm quarks, respectively. Their influence on varLambda _{c}^{+}/D^{0} ratio is individually studied. The curvature property of light-flavor quark p_{T} spectrum is the main reason of the non-monotonic p_{T} dependence of varLambda _{c}^{+}/D^{0} ratio exhibited in high multiplicity events. Moreover, the multiplicity dependence of varLambda _{c}^{+}/D^{0} ratio as the function of p_{T} is mainly because of the multiplicity dependence of light-flavor quark p_{T} spectrum. Using the light-flavor quark p_{T} spectrum obtained from experimental data of light-flavor hadrons and charm quark p_{T} spectrum obtained from FONLL and/or PYTHIA calculations, the p_{T} dependence of experimental data of varLambda _{c}^{+}/D^{0} ratio in high multiplicity events and that in low multiplicity events in pp collisions at sqrt{s}=13 TeV are reasonably understood.