Investigating $D^0$ D 0 Meson Production in P-Pb Collisions at 5.02 TeV with a Multi-Phase Transport Model

Abstract We study the production of $D^0$ D 0 meson in p+p and p-Pb collisions using the improved AMPT model considering both coalescence and independent fragmentation of charm quarks after the Cronin broadening is included. After a detailed discussion of the improvements implemented in the AMPT model for heavy quark production, we show that the modified AMPT model can provide a good description of $D^0$ D 0 meson spectra in p-Pb collisions, the $Q_{\textrm{pPb}}$ Q pPb data at different centralities and $R_{\textrm{pPb}}$ R pPb data in both mid- and forward (backward) rapidities. We also studied the effects of nuclear shadowing and parton cascade on the rapidity dependence of $D^{0}$ D 0 meson production and $R_{\textrm{pPb}}$ R pPb . Our results indicate that using the same strength of the Cronin effect (i.e $\delta $ δ value) as that obtained from the mid-rapidity data leads to a considerable overestimation of the $D^0$ D 0 meson spectra and $R_{\textrm{pPb}}$ R pPb data at high $p_{\textrm{T}}$ p T in the backward rapidity. As a result, the $\delta $ δ is determined via a $\chi ^2$ χ 2 fitting of the $R_{\textrm{pPb}}$ R pPb data across various rapidities. This work lays the foundation for a better understanding of cold-nuclear-matter (CNM) effects in relativistic heavy-ion collisions.