Observation of the Suppression of the Flux of Cosmic Rays above 4 x 1019 eV

THE PIERRE AUGER COLLABORATION.; S. J. SCIUTTO

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Año: 2008 vol. 101 p. 61101 - 61101

0031-9007

The energy spectrum of cosmic rays above 2:5 1018 eV, derived from 20 000 events recorded at the Pierre Auger Observatory, is described. The spectral index of the particle flux, J / E, at energies between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. Pierre Auger Observatory, is described. The spectral index of the particle flux, J / E, at energies between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. 2:5 1018 eV, derived from 20 000 events recorded at the Pierre Auger Observatory, is described. The spectral index of the particle flux, J / E, at energies between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. of the particle flux, J / E, at energies between 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min. 4 1018 eV and 4 1019 eV is 2:69 0:02stat 0:06syst, steepening to 4:2 0:4stat 0:06syst at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz’min.