# Multiplicity dependence of heavy-flavour correlations with charged particle and collective effects in p--Pb collisions at $\sqrt{s_\mathrm{NN}}$= 5.02 TeV with ALICE at LHC

## TL;DR

This paper investigates how heavy-flavour particle correlations with charged particles vary with multiplicity in p--Pb collisions at 5.02 TeV, revealing insights into cold nuclear matter effects and collective behavior in small systems.

## Contribution

It provides the first measurements of azimuthal correlations of prompt D-mesons and heavy-flavour decay electrons with charged hadrons as a function of multiplicity in p--Pb collisions at 5.02 TeV.

## Key findings

- Multiplicity dependence of D-meson correlations observed.
- Elliptic flow ($v_2$) of heavy-flavour decay electrons measured.
- Indications of collective effects in small collision systems.

## Abstract

Azimuthal correlation studies of heavy-flavour particles with charged particles in p--Pb collisions can give an insight into the cold nuclear matter effects \cite{Andronic:2015wma} on heavy-quark production and hadronization into heavy-flavour jets. Multiplicity-dependent measurements of angular correlations of heavy-flavour particles with charged hadrons allow us to investigate the collective behavior of the system and the initial state effects on heavy flavour hadron production. In addition, they can reveal possible modifications of the heavy-quark fragmentation and hadronization at different multiplicities. We present ALICE measurements of azimuthal correlations of prompt D-mesons with charged hadrons as a function of the multiplicity in p--Pb collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02TeV. Moreover, the elliptic flow ($v_2$) of heavy-flavour hadron decay electrons in high-multiplicity p--Pb collisions at $\sqrt{s_\mathrm{NN}}$= 5.02 TeV, obtained using correlations with charged particles, is reported.