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

The measurement of the production of prompt D⁰, D⁺, D^*+, and $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ D S + mesons in proton–lead (p–Pb) collisions at the centre-of-mass energy per nucleon pair of $$ \sqrt{s_{\mathrm{NN}}} $$ s 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 $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ D S + mesons are also reported. The $$ {\mathrm{D}}_{\mathrm{S}}^{+} $$ 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.