Speaker
Description
The Cosmic Neutrino Background (CnuB) is the oldest relic population of Standard Model particles in the Universe, carrying information from about one second after the Big Bang. Its detection would be a major milestone for cosmology and astroparticle physics. Here I will discuss a detection strategy based on the scattering of cosmic rays off relic neutrinos over cosmological distances, which can produce a boosted CnuB component extending into the energy range accessible to neutrino telescopes such as IceCube and next-generation detectors. I will then show how high-energy neutrinos from active galactic nuclei can also be used to probe dark matter. In particular, I will discuss how current data from NGC 1068 and TXS 0506+056 allow us to place leading constraints on dark matter-neutrino, dark matter-electron, and dark matter-proton interactions, and could give us a plausible hint of dark matter-photon interactions.