Components of the dilepton continuum in Pb+Pb collisions at $\sqrt{s_{{}_{NN}}}=2.76$ TeV

Abstract

The dilepton invariant mass spectrum measured in heavy-ion collisions includes contributions from important QGP probes such as thermal radiation and the quarkonium ($J/\psi$, ${\psi }^{\prime }$ and ${\rm Y}$) states. Dileptons coming from hard $q\bar{q}$ scattering, the Drell-Yan process, contribute in all mass regions. In heavy-ion colliders, such as the LHC, semileptonic decays of heavy flavor hadrons provide a substantial contribution to the dilepton continuum. The dilepton continuum can give quantitative information about heavy quark yields and their modification in the medium and thus it is important to know all different sources which populate the continuum. In the present study, we calculate $c\bar{c}$ and $b\bar{b}$ production and determine their contributions to the dilepton continuum in Pb+Pb collisions at $\sqrt{s_{{}_{NN}}}=2.76$ TeV with and without including heavy quark energy loss. We also calculate the rates for Drell-Yan and thermal dilepton production. The contributions to the continuum from these dilepton sources are studied in the kinematic ranges relevant for the LHC detectors. The relatively high $p_T$ cutoff for single leptons excludes most dileptons produced by the thermal medium. Heavy flavors are the dominant source of dilepton production in all the kinematic regimes except at forward rapidities where Drell-Yan start dominating in high mass range beyond 10 GeV/$c^2$.

18 pages, 9 figures

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• Thermal Dileptons at LHC
• Heavy-Quark Kinetics in the QGP at LHC
• Suppression of non-prompt J/psi, prompt J/psi, and Y(1S) in PbPb collisions at sqrt(sNN) = 2.76 TeV
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Cited by in corpus (6)

• Constraining heavy quark energy loss using $B$ and $D$ meson measurements in heavy ion collision at RHIC and LHC energies
• Energy loss of heavy quarks and $B$ and $D$ meson spectra in PbPb collisions at LHC energies
• Production of bottomonia states in proton+proton and heavy-ion collisions
• Quarkonia suppression in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV
• Jet-dilepton conversion in expanding quark-gluon plasma
• Photon production in Pb+Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV