Characterization of heavy-quark fragmentation via jets and correlations with ALICE

Abstract

Fragmentation functions are a key component of quantum chromodynamics (QCD) calculations based on the factorisation approach. They are typically determined from the analysis of electron-positron (e − e + ) and electron-proton (ep) collision data. Recent measurements of charmhadron spectra and of the ratios of charm-hadron abundances in pp collisions have questioned the universality of fragmentation functions across leptonic and hadronic collision systems. In these proceedings, measurements of heavy-flavour jets and angular correlations are presented, which are sensitive to the "local" hadronic environment surrounding a heavy-flavour hadron. In detail, the final measurement on the fraction of longitudinal momentum (𝑧 | | ) of jets carried by heavy-flavour hadrons is reported. The azimuthal correlations of Λ + c baryons and D mesons (D 0 , D + , and D * + ) with primary charged particles in pp collisions at √ 𝑠 = 13 TeV are reported as well. Together, these observables provide quantitative access to the angular profile, transverse momentum (𝑝 T ) and constituent-multiplicity distributions of the jets produced by the fragmentation of a heavy quark. These measurements allow to investigate the charm fragmentation and hadronisation processes in hadronic collisions, setting constraints for their modelling in event generators.