Charged Cosmic Rays are a huge background in any IACT measurement. Traditional data analysis methods involve variables that try to characterize the shape of the shower 2D pattern at the IACT focal plane. The Hillas parameters are, in this context, widely used. In this contribution an innovative method based on 3D variables, the angles and the distances (impact parameters) in space between the direction of active pixels and the EAS axis, is presented. A preliminary discussion of the effectiveness of such a method is briefly reported.

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 3 (OG part 2), pages 1321-1324