Weather corrections for a point source search at the Pierre Auger Observatory

At energies up to some 100TeV, cosmic radiation can be detected by means of particle detectors installed aboard a balloon or a satellite. At higher particle energies, the flux of the radiation drops significantly and large detection volumes are inevitable to acquire a sufficiently large amount of cosmic ray data in a short period of time. Extensive air shower experiments are exploiting the atmosphere above the actual experimental setup as a detector volume. Therefore, they are capable of recording cosmic ray data even at the highest energies. The properties of the primordial particle, however, can only be inferred from the extensive air showers, i.e. the cascades of secondary particles, that are measured by the detector setup at ground level. The performance of such experiments is thus subject to variations caused by, among other things, the instantaneous state of the atmosphere. In this thesis, a method for partly compensating the impact of these variations on the distribution of the arrival directions of cosmic rays is presented and its application to small scale anisotropy studies is investigated.