The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays.

THE PIERRE AUGER COLLABORATION (P. ABREU ET AL.). H. WAHLBERG

JOURNAL OF INSTRUMENTATION

IOP PUBLISHING LTD

Año: 2011 p. 1000 - 1003

1748-0221

We present the results of searches for dipolar-type anisotropies in different energy ranges above $2.5\times 10^{17}$ eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% $C.L.$ for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.