LUNASKA experiment observational limits on UHE neutrinos from Centaurus A and the Galactic Centre

Abstract

We present the first observational limits to the ultra-high-energy (UHE) neutrino flux from the Galactic Centre, and from Centaurus A which is the nearest active galactic nucleus. These results are based on our ‘Lunar UHE Neutrino Astrophysics using the Square Kilometre Array’ (LUNASKA) project experiments at the Australia Telescope Compact Array (ATCA). We also derive limits for the previous experiments and compare these limits with expectations for acceleration and superheavy dark matter models of the origin of UHE cosmic rays.