A new method to search for a cosmic ray dipole anisotropy

Abstract

We propose a new method to determine the dipole (and quadrupole) component of a distribution of cosmic ray arrival directions, which can be applied when there is partial sky coverage and/or inhomogeneous exposure. In its simplest version it requires that the exposure only depends on the declination, but it can be easily extended to the case of a small amplitude modulation in right ascension. The method essentially combines a ${\chi }^2$ minimization of the distribution in declination to obtain the multipolar components along the North-South axis and a harmonic Rayleigh analysis for the components involving the right ascension direction.

References in corpus (4)

• Cosmic Ray Anisotropy Analysis with a Full-Sky Observatory
• Large scale cosmic-ray anisotropy with KASCADE
• Cosmic ray spectrum and anisotropies from the knee to the second knee
• Search for Global Dipole Enhancements in the HiRes-I Monocular Data above 10^{18.5} eV

Cited by in corpus (9)

• Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory
• The Compton-Getting effect on ultra-high energy cosmic rays of cosmological origin
• The Fortuitous Latitude of the Pierre Auger Observatory and Telescope Array for Reconstructing the Quadrupole Moment
• Anisotropies and clustering of extragalactic cosmic rays
• Searches for Large-Scale Anisotropies of Cosmic Rays: Harmonic Analysis and Shuffling Technique
• A coverage independent method to analyze large scale anisotropies
• Estimating a cosmic ray detector exposure sky map under the hypothesis of seasonal and diurnal effects factorization
• The signature of local cosmic structures on the ultra-high energy cosmic ray anisotropies
• Large-Scale Distribution of Arrival Directions of Cosmic Rays Detected at the Pierre Auger Observatory Above $10$PeV