Ponente
Descripción
Charged ultra-high-energy cosmic rays are thought to be produced by astrophysical
processes such as shock acceleration. Their subsequent interactions also contribute to
the production of secondary gamma rays and neutrinos. However, physics beyond the Standard Model
at very high energy scales could also contribute to the fluxes of both charged and neutral
ultra-high-energy particles. Examples include the decay of metastable superheavy dark matter
through non-perturbative effects such as instantons. Since such processes tend to predict a
higher fraction of gamma rays and neutrinos compared to astrophysical scenarios, they
can be constrained by the stringent upper bounds on gamma-ray and neutrino fluxes
from the Pierre Auger Observatory. In this contribution, we will review these "top-down"
physics scenarios and discuss how they are probed by data from the Pierre Auger Observatory.
