Measurement of D-meson production versus multiplicity in p-Pb collisions at \(\sqrt{s_{\rm NN}}=5.02\) TeV

Abstract

The measurement of prompt D-meson production as a function of multiplicity in p–Pb collisions at \(\sqrt{s_{\rm NN}}=5.02\) TeV with the ALICE detector at the LHC is reported. D\)^0\), D\)^+\) and D\)^{*+}\) mesons are reconstructed via their hadronic decay channels in the centre-of-mass rapidity range \(-0.96 < y_{\rm cms} < 0.04\) and transverse momentum interval \(1 < p_{\rm T}<24\) GeV/c. The multiplicity dependence of D-meson production is examined by either comparing yields in p–Pb collisions in different event classes, selected based on the multiplicity of produced particles or zero-degree energy, with those in pp collisions, scaled by the number of binary nucleon–nucleon collisions (nuclear modification factor); as well as by evaluating the per-event yields in p–Pb collisions in different multiplicity intervals normalized to the multiplicity-integrated ones (relative yields). The nuclear modification factors for D\)^0\), D\)^+\) and D\)^{*+}\) are consistent with one another. The D-meson nuclear modification factors as a function of the zero-degree energy are consistent with unity within uncertainties in the measured \(p_{\rm T}\) regions and event classes. The relative D-meson yields, calculated in various \(p_{\rm T}\) intervals, increase as a function of the charged-particle multiplicity. The results are compared with the equivalent pp measurements at \(\sqrt{s}=7\) TeV as well as with EPOS 3 calculations.