Asymmetries in extensive air showers: a novel method to identify UHECR species

M. T. DOVA, M. E. MANCEÑIDO, A. G. MARIAZZI, H. WAHLBERG, F. ARQUEROS, D. GARCIA-PINTO

ASTROPARTICLE PHYSICS

Elsevier

Lugar: Amsterdam (Holanda); Año: 2009 vol. 31 p. 312 - 319

0927-6505

Azimuthal asymmetries in signals of non-vertical showers have been observed in ground arrays of water Cherenkov detectors, like Haverah Park and the Pierre Auger Observatory. The asymmetry in time distributions of arriving particles offers a new possibility for the determination of the mass composition. The dependence of this asymmetry on atmospheric depth shows a clear maximum at a position that is correlated with the primary species. In this work a novel method to determine mass composition based on these features of the ground signals is presented and a Monte Carlo study of its sensitivity is carried out.