  We extend the Maximum Likelihood method used by HiRes to study cross
correlations between a catalog of candidate astrophysical sources and Ultrahigh
Energy Cosmic Rays (UHECRs), to allow for differing source luminosities. Our
approach permits individual sources to be ranked according to their likelihood
of having emitted the correlated UHECRs. We test both old and new method by
simulations for various scenarios. We conclude that there are 9 true
correlation between HiRes UHECRs and known BLLacs, with a 6*10^-5 probability
of such a correlation arising by chance.

Astrophysics