Ultra High Energy Cosmic Rays & Super-heavy Dark Matter

We reanalyse the prospects for upcoming Ultra-High Energy Cosmic Ray experiments in connection with the phenomenology of Super-heavy Dark Matter. We identify a set of observables well suited to reveal a possible anisotropy in the High Energy Cosmic Ray flux induced by the decays of these particles, and quantify their performance via Monte Carlo simulations that mimic the outcome of near-future and next-generation experiments. The spherical and circular dipoles are able to tell isotropic and anisotropic fluxes apart at a confidence level as large as 4σ or 5σ, depending on the Dark Matter profile. The forward-to-backward flux ratio yields a comparable result for relatively large opening angles of about 40°, but it is less performing once a very large number of events is considered. We also find that an actual experiment employing these observables and collecting 300 events at 60 EeV would have a 50% chance of excluding isotropy against Super-heavy Dark Matter at a significance of at least 3σ.