Speaker: George Wojcik, University of Wisconsin-Madison
Abstract: Dark Matter (DM) and its potential interactions with the Standard Model (SM) continue to present a rich framework for model building. In the case of thermal DM of a mass between a few MeV and a few GeV, a compelling and much-explored framework is that of a dark photon/vector portal, which posits a new U(1) ``dark photon" which only couples to the SM via small kinetic mixing (KM) with the SM hypercharge. This mixing can be mediated at the one-loop level by portal matter (PM) fields which are charged under both the dark U(1) and the SM gauge group. Models with appropriate portal matter content to produce finite and calculable kinetic mixing can arise from non-minimal dark sectors, in which the dark U(1) is a subgroup of a larger gauge symmetry under which SM particles might have non-trivial representations. In this talk, I will describe a model in which the dark U(1) is unified with another popular extension to the SM gauge group, a local SU(3) flavor symmetry. The full dark/flavor symmetry group is SU(4)×U(1), incorporating the local SU(3) flavor symmetry with PM appearing as a vector-like "fourth generation" to supplement the three generations of the SM. I then discuss the phenomenology of the new extended dark gauge group at experimentally accessible energies, including non-trivial consequences of the flavor symmetry being unified with the dark sector. Note: This is a hybrid event. A zoom link will be distributed via the seminar mailing list. To join, email the organizer.