Dielectrons produced in ultra-relativistic heavy-ion collisions at the LHC provide a unique probe of the whole system evolution as they are unperturbed by final-state interactions. The dielectron continuum is extremely rich in physics sources: on top of ordinary Dalitz and resonance decays of pseudoscalar and vector mesons, thermal black-body radiation is of particular interest as it carries information about the temperature of the hot and dense system created in such collisions. Dielectron invariant-mass distribution is furthermore sensitive to medium modifications of the spectral function of short-lived vector mesons that are linked to the potential restoration of chiral symmetry at high temperatures. Correlated electron pairs from semi-leptonic charm and beauty decays provide complementary information about the heavy-quark energy loss.
In this talk, we will present an extensive summary of the LHC Run-1 results in all three collisions systems: pp, p-Pb and Pb-Pb, the former two providing crucial vacuum and cold-nuclear matter references for the latter. Furthermore, we will discuss the status of the ongoing Run-2 pp and Pb-Pb analyses with a focus on pp collisions collected with a trigger on high charged-particle multiplicities and conclude with an outlook for future measurements in Run-3 following the ALICE detector upgrades during the second long shutdown phase.
|Preferred Track||Electromagnetic Probes|