Heavy flavor production in pp and AA collisions at the LHC

TL;DR

This paper presents a comprehensive theoretical framework combining pQCD, parton shower evolution, Langevin dynamics, and fragmentation functions to predict heavy-flavor production and flow in pp and AA collisions at the LHC, matching experimental data.

Contribution

It introduces an integrated multi-step calculation method for heavy-flavor observables that improves upon previous models by combining several advanced theoretical approaches.

Findings

Good agreement with LHC Pb--Pb data for R_AA and v_2 of heavy-flavor particles.

Validation of the model against pp collision data at 7 TeV and 2.76 TeV.

Demonstrates the effectiveness of the combined pQCD and Langevin approach.

Abstract

A refined version of a multi-step calculation of heavy-flavor observables in pp and AA collisions has been developed, based on pQCD at NLO accuracy followed by parton shower evolution to describe heavy-quark production and on the relativistic Langevin equation to describe their stochastic evolution in the QCD plasma. Then, hadronization is modeled through an implementation of fragmentation functions based on pQCD and constrained by $e^{+}e^{-}$ collider data. Results of our calculations can be compared with recent measurements performed at the LHC in Pb--Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV: nuclear modification factor $R_{AA}$ of the $p_{T}$ spectra at mid-rapidity of heavy-flavor decay electrons and of exclusively reconstructed open-charm mesons at different centralities, as well as their elliptic-flow $v_{2}$($p_{T}$) in semi-central collisions. To test the validity of our setup for such studies, its predictions are also checked against the $p_{T}$ spectra measured in pp collisions at $\sqrt{s}$=7 TeV and 2.76 TeV.