A study of the Correlation of Arrival Directions of UHECRs with the
  Large Scale Structure of the Universe
  Ultrahigh energy cosmic rays (UHECRs) are believed to originate from
astrophysical sources, which should trace the large scale structure (LSS) of
the universe. On the other hand, the magnetic field in the intergalactic space
(IGMF), which also traces the LSS of the universe, deflects the trajectories of
the charged UHECRs and spoils the positional correlation of the observed UHECR
events with their true sources. To explore this problem, we studied a
simulation of the propagation of UHE protons through the magnetized LSS of the
universe, reported earlier in Das et al. (2008), in which the IGMF was
estimated based on a turbulence dynamo model (Ryu et al. 2008). Hypothetical
sources were placed inside clusters and groups of galaxies in the simulated
universe, while observers were located inside groups of galaxies that have
similar properties as the Local Group. We calculated the statistics of the
angular distance between the arrival directions of simulated UHE proton events
and the positions of candidate sources in our simulation. We compared the
statistics from our simulation with those calculated with the Auger data. We
discussed the implication of our works on the nature of the sources of UHECRs.
