Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 × 10^19 electron volts and the positions of active galactic nuclei (AGN) lying within ~75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest-energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.
|Titolo:||Correlation of the highest-energy cosmic rays with nearby extragalactic objects|
|Parole Chiave:||high energy cosmic rays ; UHECR ; AGN ; anisotropy ; extra-galactic ; Auger Observatory ; GZK ; GMF ; EGMF|
|Settore Scientifico Disciplinare:||Settore FIS/01 - Fisica Sperimentale|
|Data di pubblicazione:||9-nov-2007|
|Digital Object Identifier (DOI):||10.1126/science.1151124|
|Appare nelle tipologie:||01 - Articolo su periodico|