Large-scale-structure in the Pierre Auger Observatory data directions

Abstract

This thesis presents a method of analysis of Pierre Auger Observatory Cosmic Ray (CR) directions. I look for evidence of large-scale-structure within these CR directions. I have associated directional events by virtue of the angular proximity of their arrival directions, and within three energy ranges around the Greisen-Zatsepin-Kusmin (GZK) energy limit. I design graph theoretical algorithms to grow minimum spanning trees for these directional events and then ‘cut’ the trees along certain galactic longitudes and latitudes into ‘branches’, where I expect the galactic magnetic fields or cosmic ray point-sources to exhibit behaviours or patterns, which can be interpreted by branch features. 1,200 simulated CR directions in each energy range provide some statistical context for the Pierre Auger Observatory branch features which may be considered significant. The thesis is a preliminary study of a method of analysis of ‘regions of interest’ which later may be optimized with a full statistical ‘tuning’ analysis.