Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sNN=5.02  TeV

Charm and beauty isolation from heavy flavor decay electrons in p+p and Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV at LHC

“…There is no large difference between the ince 2 measurements at both centrality classes and collision energies, so they are combined together to help perform a better fit and extrapolation. The statistical and systematic uncertainties of measured D-meson 2 are quadratically summed and propagated into the uncertainties of D→e measured by ALICE [36] is shown as the orange squares with statistical (bars) and systematic (brackets) uncertainties, which is consistent with the result obtained in this work. Theoretical model predictions with the Langevin-hydrodynamic framework [31,32,33] shown as pink dot-dashed curves ( c→e 2 ) and violet dot-dot-dashed curves ( b→e 2 ) are consistent with results of this work at T ≳ 4 GeV/ , while they, especially the c→e 2 , deviate at low T region, which may indicate that more mechanisms need to be considered in the theoretical calculations in the low B-meson rest frame sampled by CLEO [37] applied.…”

“…It was observed that the AA of its decay daughters are less suppressed compared to those of prompt open charm mesons, which is consistent with the mass hierarchy of the parton energy loss in the medium [14,15,16,17,18]. Recently, a sizable electron 2 from beauty decays was also measured by ALICE [19], which indicates strong interactions between beauty and the medium. Since charm looks no significant difference compared with light quarks in terms of AA and 2 in RHIC and LHC energies [5,18], it is crucial to study whether beauty is sensitive to the different medium created at RHIC and LHC energies and behaves differently under different temperatures.…”

Heavy quarks and jets as probes of the QGP

“…We focus on charm since the measurements on beauty at the LHC are not yet at the same level of precision at low transverse momentum. We note, however, that they corroborate a qualitative picture within the current experimental precision [17,181,[214][215][216][217][217][218][219].…”

“…The structures in R AA and v 2 can be understood in models that embed the heavy-flavor quark interaction in a hydrodynamically expanding medium [245][246][247][248][249][250][251][252][253][254]. In addition, there is experimental evidence for a significant elliptic flow v 2 for leptons from weak decays of beauty hadrons [217,219] as shown in Fig. 17 down to relatively low transverse momentum.…”