Estudo de anisotropias de UHECR s em dados do Observatorio Pierre Auger / Study of anisotropies of cosmic rays in data from the Pierre Auger




Almost a century after the discovery of cosmic radiation, their origin, composition, acceleration and propagation mechanisms in the universe is still unknown for the ultra-high energy component ( >~ 1018 eV). The mystery grows due to the suppression (GZK cutoff) in the ux of cosmic rays with energies E >~ 6 × 10 19 eV, caused by the interaction of these particles and the cosmic microwave background, predicted ~ 40 years ago. Thus, it is expected that cosmic rays with energy above this threshold are produced in sources within ~ 200 Mpc. Since our local universe is very inhomogeneous and the magnetic rigidity of these particles is very high, it is expected that the distribution of the arrival directions of ultra-high energy cosmic rays can be correlated with the directions of their sources, reflecting the anisotropy of our local universe. In this way, anisotropy studies play crucial role in the research of cosmic radiation and understanding of the universe. In this work, small-scale anisotropy, related to the study of point sources, are studied searching for UHECR?s correlated with the giant are from SGR 1806-20 in December 2004. We have also analized directions with an excess of gamma rays with statistical significance S >4s, not associated with any known sources, reported by the JANZOS Collaboration. Also, in this thesis wavelets are applied in the detection of point sources. In the context of anisotropy related to large distributions of matter, called large scale anisotropy, we propose a new anisotropy identification method independent of catalogs, so-called MIIE. We test its efficiency through hipothesis tests and apply it to events set obtained from the Pierre Auger data


raios cosmicos anisotropy cosmic rays pierre auger observatory anisotropia

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