Energy calibration of data recorded with the surface detectors of the Pierre Auger Observatory: an update

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

Beijing

Conferencia; 32nd International Cosmic Ray Conference; 2011

The energy of the primary particles of air showers recorded using the water-Cherenkov detectors of the Pierre Auger Observatory is inferred from simultaneous measurements of showers with those detectors together with the fluorescence telescopes. The signal on the ground at 1000 m from the shower axis obtained using the water-Cherenkov detectors is related directly to the calorimetric energy measured with the telescopes. The energy assignment is therefore independent of air shower simulations except for the assumptions that must be made about the energy carried into the ground by neutrinos and muons. The correlation between the signal at the ground and the calorimetric energy is used to derive a calibration curve. Taking advantage of increased statistics with respect to previous publications we present an update and improvement of the method used to determine the energy scale. The systematic uncertainties of the calibration procedure are addressed.