Small-scale anisotropy of cosmic rays with energies above 3×1018 eV based on data from the Yakutsk EAS facility

We analyze the directions of the arrival of cosmic rays with energies E0≥3×1018 eV and zenith angles θ≤45° recorded by the Yakutsk extensive air shower (EAS) facility during 1974–2000. They are shown to have a small-scale structure with scale sizes of 5°–10°. Enhanced particle fluxes compared to the expected levels for random distributions at (4–5)σ are observed from the Galactic and Supergalactic planes.