Ultrahigh energy cosmic-ray propagation in the Galaxy:: Clustering versus isotropy

Recently, the Akeno Giant Air Shower Array Collaboration presented data suggesting a significant clustering of ultrahigh energy cosmic rays coming from the outer Galaxy region. In this paper we calculate expected cosmic-ray arrival distributions for several simple source location scenarios that bracket the more realistic ones and investigate the possibility of clustering and correlation effects. The role of the Galactic magnetic field is discussed in detail.