Production of D-Mesons in p+p and p+Pb Collisions at LHC Energies

We present theoretical model comparison with published ALICE results for D-mesonsD-meson ( ${\text {D}}^0$ , ${\text {D}}^+$ and ${\text {D}}^{*+}$ ) in p+p collisions at $\sqrt{s} =$ 7 TeV and p+Pb collisions at $\sqrt{s_\mathrm{{NN}}} =$ 5.02 TeV. The calculations from HIJING and AMPT are showing prominent cold nuclear matter effects such as shadowing, EMC (EM Collab., J. Ashman et al., Phys. Lett. B 202:603, (1988), EM Collab., M. Arneodo et al., Phys. Lett. B 211:493, (1988), [1]), and multi-parton scattering effects, for the entire $p_\mathrm{{T}}$ range. In caseCold nuclear matter of NLO with additional momentum broadening effect are closer to the trend of the data within its error bars. FONLL gives very small shadowing effect for $p_\mathrm{{T}} < 10$ GeV/c.