Measurement of the UHECR energy spectrum from hybrid data of the Pierre Auger Observatory

THE PIERRE AUGER COLLABORATION (AUTOR 384 DE 427); M. J. TUEROS

Mérida, México

Conferencia; 30th International Cosmic Ray Conference; 2007

Instituto de Geofísica, UNAM

More than two years of fluorescence detector data collected in coincidence with at least one station of the surface detector array (“hybrid data”) are used to measure the flux and energy spectrum of cosmic rays above about 1E18 eV. The hybrid measurement extends towardslower energies the spectrum measured with the surface detector data only, and provides a cross- check with an independent data set. The determination of the fluorescence detector aperture and of its live-time, which is the major aspect of this measurement, is illustrated in detail. Our current estimate of the corresponding systematic uncertainties are given.