Constraining Multiple Kinetically Mixed Dark Photons

Abstract

Extra U(1) gauge bosons under which Standard Model particles are uncharged, aka dark photons, are a simple and well-motivated extension of the Standard Model. There could be a single, but also several or even many such dark photons. However, most studies consider only a single dark photon. Here, we want to look at the more general case of multiple dark photons interacting with the Standard Model via kinetic mixing. We consider a range of standard probes, Cavendish experiments, light-shining-through-walls experiments, as well as energy loss in stars. To explore the rather high-dimensional parameter space of the masses and the kinetic mixing matrix, we pursue a statistical approach, considering different distributions for the kinetic mixing parameters.