Speaker
Description
Low mass dielectron measurements in ultra-relativistic heavy-ion collisions
bring an important information on the properties of the hot and dense QCD medium and whole space-time evolution of the medium created in heavy-ion collisions.
Dielectrons in the mass range below 1 GeV/$c^2$, are from ordinary Dalitz and resonance decays of pseudoscalar and vector mesons. Dielectron invariant mass from short-lived vector mesons is sensitive to medium modifications of the spectral functions that are related to the chiral symmetry restoration at high temperatures. Dielectrons in the intermediate mass region from 1 to 3 GeV/$c^2$
originate mainly from the correlated electron pairs from semi-leptonic decays
of charm and beauty quarks, which carry the information on the heavy-quark energy loss. Thermal radiations from the medium contribute to the dielectron yields in a broad mass range and provide information on the thermodynamical properties of the medium.
Low mass dielectrons have been measured with the ALICE detector at the LHC in pp collisions at $\sqrt{s}$ = 7 TeV and p-Pb collisions at $sqrt{s_{\rm NN}}$ = 5.02 TeV to study and disentangle effects due to the cold nuclear matter. In Pb-Pb collisions, the low mass dielectron mass spectra are measured for different pair $p_{\rm T}$ ranges.
In this talk, we will present a review of LHC Run-1 results from pp, p-Pb, and Pb-Pb collisions and we will discuss the production of virtual photons and heavy quarks. Furthermore, we will discuss the latest results of the analysis of Run-2 pp collisions at 13 TeV and report on the development of our analysis employing multivariable analysis techniques.
| Experimental Collaboration | ALICE Collaboration |
|---|
