A novel method for the determination of the EAS missing energy for golden hybrid events at the Pierre Auger Observatory

A. G. MARIAZZI; M. J. TUEROS

Auger Gap Note

The Pierre Auger Collaboration

Lugar: Malargüe; Año: 2010 p. 1 - 14

0395-2037

In this note we present a new approach for the determination of the missing energy in extensive air showers. This approach takes advantage of the hybrid nature of the Pierre Auger Observatory, using the signal at 1000 m from the shower core and the atmospheric slant depth of the shower maximum to provide a robust estimation of the missing energy, reducing the systematic uncertainties that this correction introduces in the determination of the primary energy by a factor of two. We applied this method to estimate the missing energy of a sample of golden hybrid events and found that the official reconstruction underestimates the missing energy, introducing a 4% bias in the determination of the primary energy. With the technique proposed in this note the before-mentioned bias is removed. For events in which this method cannot be applied, we give a new parameterization of the average missing energy as a function of the shower calorimetric energy.