Ultra-high energy cosmic rays: Are they isotropic?

From the analysis of Akeno Giant Air Shower Array (AGASA) data above 4 x 10 (19) eV, we show that the ultra-high energy cosmic ray flux is neither pure ly isotropic nor reflects the expected anisotropy from a pure source distri bution that maps large-scale structure in the local universe. The arrival d istribution seems to be the result of a mixture of fluxes (e.g., dark matte r halo plus large-scale structure) or the superposition of direct and diffu se radiation field components, respectively. Another viable option is an ar bitrary extragalactic flux reprocessed by a magnetized galactic wind model, as recently proposed in the literature.