  Tidal disruptions are extremely powerful phenomena that have been designated
as candidate sources of ultra-high-energy cosmic rays. The disruption of a star
by a black hole can naturally provide protons and heavier nuclei, which can be
injected and accelerated to ultra-high energies within a jet. Inside the jet,
accelerated nuclei are likely to interact with a dense photon field, leading to
a significant production of neutrinos and secondary particles. We model
numerically the propagation and interactions of high-energy nuclei in jetted
tidal disruption events in order to evaluate consistently their signatures in
cosmic rays and neutrinos. We propose a simple model of the light curve of
tidal disruption events, consisting of two stages: a high state with bright
luminosity and short duration and a medium state, less bright and longer
lasting. These two states have different impacts on the production of cosmic
rays and neutrinos. In order to calculate the diffuse fluxes of cosmic rays and
neutrinos, we model the luminosity function and redshift evolution of jetted
tidal disruption events. We find that we can fit the latest ultra-high-energy
cosmic-ray spectrum and composition results of the Auger experiment for a range
of reasonable parameters. The diffuse neutrino flux associated with this
scenario is found to be subdominant, but nearby events can be detected by
IceCube or next-generation detectors such as IceCube-Gen2.
