Investigating D⁰ meson production in p-Pb collisions at 5.02 TeV with a multi-phase transport model

We study the production of D⁰ 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 D⁰ D 0 meson spectra in p -Pb collisions, the QpPb Q pPb data at different centralities and RpPb 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 D⁰ D 0 meson production and RpPb R pPb . Our results indicate that using the same strength of the Cronin effect (i.e δ δ value) as that obtained from the mid-rapidity data leads to a considerable overestimation of the D⁰ D 0 meson spectra and RpPb R pPb data at high pT p T in the backward rapidity. As a result, the δ δ is determined via a χ ² χ 2 fitting of the RpPb 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.