Measurement of D0 -meson + hadron two-dimensional angular correlations in Au+Au collisions at

J. Adam¹,

L. Adamczyk²,

J. R. Adams³

et al.

Abstract

Azimuthal anisotropies of muons from charm and bottom hadron decays are measured in Pb+Pb collisions at √ s NN = 5.02 TeV. The data were collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2018 with integrated luminosities of 0.5 nb −1 and 1.4 nb −1 , respectively. The kinematic selection for heavy-flavor muons requires transverse momentum 4 < p T < 30 GeV and pseudorapidity |η| < 2.0. The dominant sources of muons in this p T range are semi-leptonic decays of charm and bottom hadrons. These heavy-flavor muons are separated from light-hadron decay muons and punch-through hadrons using the momentum imbalance between the measurements in the tracking detector and in the muon spectrometers. Azimuthal anisotropies, quantified by flow coefficients, are measured via the eventplane method for inclusive heavy-flavor muons as a function of the muon p T and in intervals of Pb+Pb collision centrality. Heavy-flavor muons are separated into contributions from charm and bottom hadron decays using the muon transverse impact parameter with respect to the event primary vertex. Non-zero elliptic (v 2) and triangular (v 3) flow coefficients are extracted for charm and bottom muons, with the charm muon coefficients larger than those for bottom muons for all Pb+Pb collision centralities. The results indicate substantial modification to the charm and bottom quark angular distributions through interactions in the quark-gluon plasma produced in these Pb+Pb collisions, with smaller modifications for the bottom quarks as expected theoretically due to their larger mass.

Jet fragmentation via azimuthal angular correlations of heavy flavor decay electrons in pp, p--Pb, and Pb--Pb collisions using PYTHIA8+Angantyr

“…There is also some correlation between FSR+ISR and MPI processes since initial-and final-state radiations are generated from all the parton interactions occurring in the collision and are thus enhanced in the presence of MPI. The recent measurement of angular correlations between D mesons and charged particles by the STAR collaboration shows a significant modification of the near-side peak width and associated yield, which increases from peripheral to central Au-Au collisions [23]. Similar measurements were later carried out by LHC, which investigated the possible modifications in jet properties due to the medium effects [24].…”

Radial profile of bottom quarks in jets in high-energy nuclear collisions *

“…Owing to their large mass ( ) and early creation time, heavy quarks are witnesses of the entire QGP evolution and are therefore viewed as ideal hard probes to constrain the transport properties of QGP and also improve our understanding of in-medium heavy quark evolution. As new favorites of observables in heavy-ion collisions (HIC), the nuclear modification factor [19][20][21], collective flow [22][23][24][25] of heavy flavored mesons, and + hadron correlations [26] have been extensively measured experimentally and successfully modeled in theory [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45]; however, there are still some important key questions to be addressed [46]. For reviews, see Refs.…”

Azimuthal correlations of prompt D mesons with charged particles in pp and p–Pb collisions at $$\varvec{\sqrt{s_\mathrm{NN}}} = 5.02\ \hbox {TeV}$$

“…The interaction of heavy quarks (charm and beauty) with the QGP should affect the angular-correlation function [1,18,19]. First measurements performed at RHIC and the LHC showed modifications of the correlation function in nucleus-nucleus collisions when the trigger was a heavy-flavour particle, where a suppression of the away-side correlation peak and an enhancement of the near-side correlation peak for associated particles with p T < 2 GeV/c was observed [20,21]. A comparison of the results in nucleus-nucleus collisions to those in pp collisions, along with a successful description by models, would allow the modifications of the correlation function to be related to the in-medium heavy-quark dynamics [18,22,23].…”