Speaker
Description
Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons,
leading to multiple photon-induced processes. This talk presents a series of measurements of such
processes performed by the ATLAS Collaboration. New measurements of exclusive dilepton production
(electron, muon, and tau pairs) are discussed. Furthermore, the tau-pair production measurements
can constrain the tau lepton’s anomalous magnetic dipole moment. High statistics
measurements of light-by-light scattering shown in this talk provide a precise and unique opportunity to investigate extensions of the Standard Model, such as the presence of axion-like particles.
Presented measurements of muon pairs produced via two-photon scattering processes in hadronic Pb+Pb collisions provide a novel test of strong-field QED by exploiting correlations between the lepton pair and second-order event-plane, which can potentially be a sensitive electromagnetic
probe of the quark-gluon plasma. Results are compared with recent theory calculations.
