Large scale distribution of arrival directions of cosmic rays detected above $10^{18}$ eV at the Pierre Auger Observatory

Abstract

A thorough search for large scale anisotropies in the distribution of arrival directions of cosmic rays detected above $10^{18}$ eV at the Pierre Auger Observatory is presented. This search is performed as a function of both declination and right ascension in several energy ranges above $10^{18}$ eV, and reported in terms of dipolar and quadrupolar coefficients. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Assuming that any cosmic ray anisotropy is dominated by dipole and quadrupole moments in this energy range, upper limits on their amplitudes are derived. These upper limits allow us to challenge an origin of cosmic rays above $10^{18}$ eV from stationary galactic sources densely distributed in the galactic disk and emitting predominantly light particles in all directions.

41 pages, 12 figures

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Cited by in corpus (19)

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• Searches for Large-Scale Anisotropy in the Arrival Directions of Cosmic Rays Detected above Energy of $10^{19}$ eV at the Pierre Auger Observatory and the Telescope Array
• Simulations of ultra-high Energy Cosmic Rays in the local Universe and the origin of Cosmic Magnetic Fields
• Cosmic-ray anisotropies in right ascension measured by the Pierre Auger Observatory
• Escape model for Galactic cosmic rays and an early extragalactic transition
• Progress in high-energy cosmic ray physics
• A search for point sources of EeV photons
• A Targeted Search for Point Sources of EeV Neutrons
• Impact of atmospheric effects on the energy reconstruction of air showers observed by the surface detectors of the Pierre Auger Observatory
• Cosmic Rays around $10^{18}$eV: Implications of Contemporary Measurements on the Origin of the Ankle Feature
• Determination of the Cosmic-Ray Chemical Composition: Open Issues and Prospects
• Sensitivity of full-sky experiments to large scale cosmic ray anisotropies
• The Fortuitous Latitude of the Pierre Auger Observatory and Telescope Array for Reconstructing the Quadrupole Moment
• Mass composition of cosmic rays determined by muon fraction with ${\epsilon }_{thr.}\ge$ 1 GeV in air showers with energy greater than 5 EeV
• Large Scale Anisotropy of Cosmic Rays and Directional Neutrino Signals from Galactic Sources
• Cosmic-Ray Convection-Diffusion Anisotropy
• Effects of galactic magnetic field on the UHECR correlation studies with starburst galaxies
• Ultra-high energy cosmic rays with UFA-15 source model in Bumblebee gravity theory