Measurement of prompt D0, D+, D*+, and D S + $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ production in p–Pb collisions at s NN $$ \sqrt{{\mathrm{s}}_{\mathrm{NN}}} $$ = 5.02 TeV

Abstract

Abstract The measurement of the production of prompt D0, D+, D*+, and D S + $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons in proton–lead (p–Pb) collisions at the centre-of-mass energy per nucleon pair of s NN $$ \sqrt{s_{\mathrm{NN}}} $$ = 5.02 TeV, with an integrated luminosity of 292 ± 11 μb −1, are reported. Differential production cross sections are measured at mid-rapidity (−0.96 < y cms < 0.04) as a function of transverse momentum (p T) in the intervals 0 < p T < 36 GeV/c for D0, 1 < p T < 36 GeV/c for D+ and D*+, and 2 < p T < 24 GeV/c for D+ mesons. For each species, the nuclear modification factor R pPb is calculated as a function of p T using a proton-proton (pp) ref- erence measured at the same collision energy. The results are compatible with unity in the whole p T range. The average of the non-strange D mesons R pPb is compared with theoretical model predictions that include initial-state effects and parton transport model predictions. The p T dependence of the D0, D+, and D*+ nuclear modification factors is also reported in the interval 1 < p T < 36 GeV/c as a function of the collision centrality, and the central-to-peripheral ratios are computed from the D-meson yields measured in different centrality classes. The results are further compared with charged-particle measurements and a similar trend is observed in all the centrality classes. The ratios of the p T-differential cross sections of D0, D+, D*+, and D S + $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ mesons are also reported. The D S + $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ and D+ yields are compared as a function of the charged-particle multiplicity for several p T intervals. No modification in the relative abundances of the four species is observed with respect to pp collisions within the statistical and systematic uncertainties.

Keywords

• Heavy Ion Experiments