Speaker
Description
Electron-positron pairs are an excellent probe to investigate the properties of the Quark-Gluon Plasma (QGP) created in ultra-relativistic heavy-ion collisions. Because they are produced at all stages of the collision and do not interact strongly with the medium, their spectra reflect the entire space-time evolution of the system. At low invariant mass ($m_{\textrm{ee}} < 1.2 \textrm{ GeV/c}^2$), the dielectron production is sensitive to the properties of vector mesons in the dense medium which is related to the predicted restoration of the chiral symmetry. In the intermediate-mass region ($1.2 < m_{\textrm{ee}} < 2.9 \textrm{ GeV/c}^{2}$), the dielectron continuum gives further insight into the heavy-quark energy loss in the QGP via the measurement of correlated electron-positron pairs from charm- and beauty- hadron decays. Finally, contributions of thermal radiation from the medium, both during the partonic and the hadronic phases, are predicted in a broad mass range and provide information on the temperature of the system.
In this poster, the status of the dielectron measurements in Pb-Pb collisions at $\sqrt{s_{\textrm{NN}}} = 5.02 \textrm{ TeV}$ with ALICE will be presented. In order to interpret the data, the findings will be compared to the expected yield of known hadronic sources, i.e. the hadronic cocktail, as a function of the invariant mass and pair transverse momentum. Finally, the status of the measurement of virtual direct photons and modifications of the dielectron yield in Pb-Pb collisions will be discussed.
| Content type | Experiment |
|---|---|
| Collaboration | ALICE |
| Centralised submission by Collaboration | Presenter name already specified |
