Medium-induced modification of azimuthal correlations of electrons from heavy-flavor hadron decays with charged particles in Pb--Pb collisions at $\sqrt{s_{\mathrm{NN}}=5.02}$ TeV

Abstract

The azimuthal-correlation distributions between electrons from the decays of heavy-flavor hadrons and associated charged particles in Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV are reported for the 0$-$10% and 30$-$50% centrality classes. This measurement provides access to the jet-like correlation observables in the heavy-flavor sector in Pb$-$Pb collisions. The analysis is performed for trigger electrons from heavy-flavor hadron decays with transverse momentum $4<p_{\mathrm{T}}^{\mathrm{e}}<16\mathrm{GeV}/c$, considering associated particles within the transverse-momentum range $1<p_{\mathrm{T}}^{\mathrm{assoc}}<7$ $\mathrm{GeV}/c$, and a pseudorapidity difference of $|\Delta \eta |<1$ between the trigger electron and associated particles. The per-trigger nuclear modification factor ($I_{\mathrm{AA}}$) is calculated to compare the near- and away-side peak yields to those in pp collisions at $\sqrt{s}=5.02$ TeV. In 0$-$10% central collisions, the $I_{\mathrm{AA}}$ indicates a hint of enhancement of associated-particle yields with $p_{\mathrm{T}}<3$ GeV/$c$ on the near side, and a suppression of yields with $p_{\mathrm{T}}>4$ GeV/$c$ on the away side. The $I_{\mathrm{AA}}$ for electron triggers from heavy-flavor hadron decays is compared with that for light-flavor and strange-particle triggers to investigate the dependence on different fragmentation processes and parton-medium dynamics, and is found to be the same within uncertainties.

35 pages, 10 captioned figures, 2 tables, authors from page 29, published version, figures at http://alice-publications.web.cern.ch/node/12665