Search for sidereal modulation of the arrival directions of events recorded at the Pierre Auger Observatory

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

Lodz, Polonia

Conferencia; 31th International Cosmic Ray Conference; 2009

Using data collected by the Pierre AugerObservatory from 1 January 2004 until 31 March2009, we search for large scale anisotropies in differentenergy windows above 2 · 1017 eV. A Fourieranalysis shows the presence of a » 3% modulation atthe solar frequency, arising from modulations of thearray exposure and weather effects on the showers.We study the sidereal anisotropies using a Rayleighmethod which accounts for these effects, and theEast-West differential method which is largely independentof them. No significant anisotropies areobserved, resulting in bounds on the first harmonicamplitude at the 1% level at EeV energies