Date Dec 7, 2020, 2:30 pm – 2:30 pm Location Via Zoom Share on X Share on Facebook Share on LinkedIn Speaker William McCormack Affiliation Lawrence Berkeley National Laboratory Details William McCormack Event Description After the Higgs mechanism breaks the SU(2)xU(1) symmetry of the Electroweak sector of the Standard Model, we find trilinear and quartic terms coupling photons and W bosons. This leads to the experimentally testable prediction that two colliding high-energy photons can convert into two W bosons. Measuring this interaction would be a unique probe of the structure of Electroweak physics and can place strong constraints on anomalous quartic gauge couplings. While there are no existing photon colliders of sufficient energy to permit WW production, it should occur in the collisions of slightly-virtual photons emitted by protons at the LHC. The ATLAS collaboration has recently established an observation of this process using LHC Run 2 proton-proton data with an observed significance of 8.4 sigma. This talk will cover some of the unique challenges that arise when using the LHC as a photon collider during proton-proton running at nominal pileup and their solutions. I will also present prospects for future photon-fusion measurements with ATLAS using techniques such as low-pT tracking. https://princeton.zoom.us/j/97556238230 Meeting ID: 975 5623 8230