Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with Zenith angles up to 80 degrees.

THE PIERRE AUGER COLLABORATION.; S. J. SCIUTTO

ASTROPHYSICAL JOURNAL

IOP PUBLISHING LTD

Lugar: Londres; Año: 2015 vol. 802 p. 111 - 122

0004-637X

We present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rayswith energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenithangle between 60° and 80°. We perform two Rayleigh analyses, one in the right ascension and one in the azimuthangle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largestdeparture from isotropy appears in the E > 8 EeV energy bin, with an amplitude for the first harmonic in rightascension r1a = (4.4  1.0) ´ 10-2, that has a chance probability P(⩾ra) = 6.4 ´ 10- 15, reinforcing the hintpreviously reported with vertical events alone.