  Topological defects, particularly cosmic strings, can provide a mechanism to
produce particles with energies of the order 10^21 eV and higher. Here, we
report on order of magnitude calculations of fluxes from a cosmic string
network which evolves according to a new scenario according to which the main
channel for energy loss is the particle production rather than gravitational
radiation. We compare the predicted fluxes for protons (anti-protons) and
neutrinos (anti-neutrinos) with observations of extremely high energy cosmic
rays.
