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 × 1019 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.
Correlation of the highest energy cosmic rays with nearby extragalactic objects / Guarino, Fausto; D'Urso, Domenico; M., Ambrosio; Aramo, Carla; DELLA SELVA, Angelo; Miele, Gennaro; Pisanti, Ofelia; Valore, Laura; Auger, Collaboration. - In: SCIENCE. - ISSN 0036-8075. - STAMPA. - 318:(2007), pp. 938-943. [10.1126/science.1151124]
Correlation of the highest energy cosmic rays with nearby extragalactic objects
GUARINO, FAUSTO;D'URSO, DOMENICO;ARAMO, CARLA;DELLA SELVA, ANGELO;MIELE, GENNARO;PISANTI, OFELIA;VALORE, LAURA;
2007
Abstract
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 × 1019 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.File | Dimensione | Formato | |
---|---|---|---|
Science.pdf
non disponibili
Tipologia:
Documento in Post-print
Licenza:
Accesso privato/ristretto
Dimensione
1.54 MB
Formato
Adobe PDF
|
1.54 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.