Dr Adrian Bevan (Queen Mary University of London (UK))
Recent astrophysical observations have motivated interest in models with a new, dark sector containing GeV-scale gauge and Higgs bosons. In such models, dark-sector photons typically mix with the standard-model photon, enabling their detection in e+e- collisions at BABAR, with very little background in many of the channels. We present searches for a dark-sector photon and a dark-sector Higgs boson and set stringent limits on the parameters of the model. One way to present our results is that if the dark-sector U(1) coupling is similar to the standard-model electromagnetic coupling, our limits on the mixing between the standard model and the dark sector are tighter than previous limits by up to two orders of magnitude, depending on the masses of the dark Higgs and dark boson.