# Azimuthal correlations of D-mesons in $p$+$p$ and $p$+Pb collisions at LHC energies

## TL;DR

This paper investigates azimuthal correlations of D mesons in proton-proton and proton-lead collisions at LHC energies, analyzing effects of cold nuclear matter and providing predictions for future medium modification studies.

## Contribution

It introduces a detailed analysis of D meson correlations, including predictions for D-Dbar pairs with higher-order QCD calculations and cold nuclear matter effects.

## Key findings

- Correlation sensitivity to cold nuclear medium effects
- Predictions for D-Dbar azimuthal correlations in p+p and p+Pb
- Baseline for studying medium modifications in heavy-ion collisions

## Abstract

We study the correlations of D mesons produced in $p$+$p$ and $p$+Pb collisions. These are found to be sensitive to the effects of the cold nuclear medium and the transverse momentum ($p_T$) regions we are looking into. In order to put this on a quantitative footing, as a first step we analyse the azimuthal correlations of D meson-charged hadron(Dh), and then predict the same for D meson -anti D meson ($D\overline{D}$) pairs in $p$+$p$ and $p$+Pb collisions with strong coupling at leading order $\cal{O}$($\alpha_{s}^{2}$) and next to leading order $\cal{O}$($\alpha_{s}^{3}$) which includes space-time evolution (in both systems), as well cold nuclear matter effects (in $p$+Pb). This also sets the stage and baseline for the identification and study of medium modification of azimuthal correlations in relativistic collision of heavy nuclei at the Large Hadron Collider.