Measurement of the cosmic ray energy spectrum above 1018 eV using the Pierre Auger Observatory

PIERRE AUGER COLLABORATION (J. ABRAHAM, ... , A. MARIAZZI, ET AL)

Lodz, Polonia

Conferencia; 31th International Cosmic Ray Conference; 2009

The flux of cosmic rays above 1018 eV has been measured with unprecedented precision using the Pierre Auger Observatory. Two analysis techniques have been used to extend the spectrumdownwards from 3 × 1018 eV, with the lower energies being explored using a novel technique that exploits the hybrid strengths of the instrument.The systematic uncertainties, and in particular the influence of the energy resolution on the spectral shape, are addressed. The spectrum can be described by a broken power-law of index 3.3 below theankle which is measured at lg(Eankle/eV) = 18.6. Above the ankle the spectrum is described by a power-law / E−2.6 and a flux suppression with lg(E1/2/eV) = 19.6.