Asymmetries observed in giant air showers using water Cherenkov detectors

Evidence of azimuthal asymmetries in the time structure and signal size has been found in non-vertical showers as a function of zenith angle. These asymmetries arise because of the different paths traveled by particles in the upper and lower sides of the plane perpendicular to the shower axis to rea...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Dova, María Teresa, The Pierre Auger Collaboration
Formato: Objeto de conferencia
Lenguaje:Español
Publicado: 2003
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/81753
http://inspirehep.net/record/626368
Aporte de:
Descripción
Sumario:Evidence of azimuthal asymmetries in the time structure and signal size has been found in non-vertical showers as a function of zenith angle. These asymmetries arise because of the different paths traveled by particles in the upper and lower sides of the plane perpendicular to the shower axis to reach detectors at the same axial distances. The shower particles are differentially attenuated as they traverse the atmosphere. Furthermore, most particles are not propagating strictly in the shower direction but are on average going away from the axis. This geometrical projection effect also contributes to the final asymmetry. These novel observations must be understood for parameterisation of the lateral distribution function. Additionally, the asymmetry in time distributions offers a new possibility for the determination of the mass composition because its magnitude is strongly dependent on the fraction of electromagnetic signal at the observation level. The asymmetries found in data collected from the Engineering Array of the Auger Observatory will be compared with Monte Carlo data.