Measurement of prompt D0, D+, D*+, and DS⁺ production in p–Pb collisions at √sNN = 5.02 TeV

A bstract The measurement of the production of prompt D 0 , D + , D *+ , and DS⁺ D S + mesons in proton–lead (p–Pb) collisions at the centre-of-mass energy per nucleon pair of √sNN s NN = 5 . 02 TeV, with an integrated luminosity of 292 ± 11 μ b − 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 D 0 , 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 D 0 , 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 D 0 , D + , D *+ , and DS⁺ D S + mesons are also reported. The DS⁺ D 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.