Cosmic Ray Anisotropy Analysis with a Full-Sky Observatory

Abstract

A cosmic ray observatory with full-sky coverage can exploit standard anisotropy analysis methods that do not work if part of the celestial sphere is never seen. In particular, the distribution of arrival directions can be fully characterized by a list of spherical harmonic coefficients. The dipole vector and quadrupole tensor are of special interest, but the full set of harmonic coefficients constitutes the anisotropy fingerprint that may be needed to reveal the identity of the cosmic ray sources. The angular power spectrum is a coordinate-independent synopsis of that fingerprint. The true cosmic ray anisotropy can be measured despite non-uniformity in celestial exposure, provided the observatory is not blind to any region of the sky. This paper examines quantitatively how the accuracy of anisotropy measurement depends on the number of arrival directions in a data set.

23 pages, 6 figures. Submitted to Astroparticle Physics

References in corpus (2)

• GZK Violation - a Tempest in a (Magnetic) Teapot?
• Ultra High Energy Cosmic Rays from Cosmological Relics

Cited by in corpus (119)

• Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei
• Measurement of the cosmic-ray energy spectrum above $2.5\times 10^{18}$ eV using the Pierre Auger Observatory
• Ultra-High Energy Cosmic Ray Probes of Large Scale Structure and Magnetic Fields
• Ultra-High-Energy Cosmic Rays
• Cosmic Neutrino Pevatrons: A Brand New Pathway to Astronomy, Astrophysics, and Particle Physics
• Ultra-High Energy Cosmic Rays in a Structured and Magnetized Universe
• Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger Observatory
• 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
• Heavy decaying dark matter and IceCube high energy neutrinos
• Searching for a Correlation Between Cosmic-Ray Sources Above 10^{19} eV and Large-Scale Structure
• Constraining heavy decaying dark matter with the high energy gamma-ray limits
• Gamma-ray bounds from EAS detectors and heavy decaying dark matter constraints
• The Small Scale Anisotropies, the Spectrum and the Sources of Ultra High Energy Cosmic Rays
• Ultra-High Energy Cosmic Rays, Spiral galaxies and Magnetars
• All-Sky Measurement of the Anisotropy of Cosmic Rays at 10 TeV and Mapping of the Local Interstellar Magnetic Field
• Ultra-high energy Neutrinos from Centaurus A and the Auger hot spot
• Large scale distribution of arrival directions of cosmic rays detected above $10^{18}$ eV at the Pierre Auger Observatory
• Testing a reported correlation between arrival directions of ultrahigh-energy cosmic rays and a flux pattern from nearby starburst galaxies using Telescope Array data
• On Active Galactic Nuclei as Sources of Ultra-High Energy Cosmic Rays
• Ultrahigh Energy Nuclei in the Turbulent Galactic Magnetic Field
• Lower limits on ultrahigh-energy cosmic ray and jet powers of TeV blazars
• Cosmic Ray Astronomy
• Testing large-scale (an)isotropy of ultra-high energy cosmic rays
• Cosmic Magnetic Fields and Their Influence on Ultra-High Energy Cosmic Ray Propagation
• The footprint of large scale cosmic structure on the ultra-high energy cosmic ray distribution
• Search for signatures of magnetically-induced alignment in the arrival directions measured by the Pierre Auger Observatory
• PARSEC: A Parametrized Simulation Engine for Ultra-High Energy Cosmic Ray Protons
• The Anisotropy of the Ultra-High Energy Cosmic Rays
• Clustering of ultra-high energy cosmic ray arrival directions on medium scales
• The effect of the geomagnetic field on cosmic ray energy estimates and large scale anisotropy searches on data from the Pierre Auger Observatory
• Centaurus A as the Source of ultra-high energy cosmic rays?
• Performance and science reach of POEMMA for ultrahigh-energy particles
• Large Scale Magnetic Fields and the Number of Cosmic Ray Sources above 10^(19) eV
• Cross-Correlation between UHECR Arrival Distribution and Large-Scale Structure
• Modeling the Spectral Energy Distribution of the radio galaxy IC310
• First implications of Tibet AS${}_{\gamma }$ data for heavy dark matter
• Neutrino, $\gamma$-ray and cosmic ray fluxes from the core of the closest radio galaxies
• Anisotropy expectations for ultra-high-energy cosmic rays with future high statistics experiments
• Implications to Sources of Ultra-high-energy Cosmic Rays from their Arrival Distribution
• Does Galactic Magnetic Field Disturb the Correlation of the Highest Energy Cosmic Rays with their Sources?
• The Centaurus A Ultrahigh-Energy Cosmic Ray Excess and the Local Extragalactic Magnetic Field
• An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations
• Global anisotropy of arrival directions of ultra-high-energy cosmic rays: capabilities of space-based detectors
• Multi-resolution anisotropy studies of ultrahigh-energy cosmic rays detected at the Pierre Auger Observatory
• Generalised 3D-reconstruction method of a dipole anisotropy in cosmic-ray distributions
• Search for Spatial Correlations of Neutrinos with Ultra-High-Energy Cosmic Rays
• Ultrahigh-energy cosmic ray interactions as the origin of very high energy $\gamma -$rays from BL Lacs
• On the relation between the neutrino flux from Centaurus A and the associated diffuse neutrino flux
• Angular correlation of cosmic neutrinos with ultrahigh-energy cosmic rays and implications for their sources
• UHECR arrival directions in the latest data from the original Auger and TA surface detectors and nearby galaxies
• On the anisotropy in the arrival directions of ultra-high-energy cosmic rays
• Propagation of Ultra-High-Energy Cosmic Ray Nuclei in Cosmic Magnetic Fields and Implications for Anisotropy Measurements
• Hadronically decaying heavy dark matter and high-energy neutrino limits
• Gamma-Ray Bursts and Magnetars as Possible Sources of Ultra High Energy Cosmic Rays: Correlation of Cosmic Ray Event Positions with IRAS Galaxies
• Estimates of multipolar coefficients to search for cosmic ray anisotropies with non-uniform or partial sky coverage
• Statistical Analysis of the Correlation between Active Galactic Nuclei and Ultra-High Energy Cosmic Rays
• Decaying neutron propagation in the Galaxy and the Cosmic Ray anisotropy at 1 EeV
• Isotropy constraints on powerful sources of ultrahigh-energy cosmic rays at $10^{19}$ eV
• Update on tests of the Cen A neutron-emission model of highest energy cosmic rays
• Clustering properties of ultrahigh energy cosmic rays and the search for their astrophysical sources
• The UHECR dipole and quadrupole in the latest data from the original Auger and TA surface detectors
• Full-Sky Search for Ultra High Energy Cosmic Ray Anisotropies
• Angular Power Spectrum Estimation of Cosmic Ray Anisotropies with Full or Partial Sky Coverage
• A correlation between the highest energy cosmic rays and nearby active galactic nuclei detected by Fermi
• Search for patterns by combining cosmic-ray energy and arrival directions at the Pierre Auger Observatory
• Identification of Patterns in Cosmic-Ray Arrival Directions using Dynamic Graph Convolutional Neural Networks
• Full sky harmonic analysis hints at large UHECR deflections
• A Search for Correlation of Ultra-High Energy Cosmic Rays with IRAS-PSCz and 2MASS-6dF Galaxies
• TeV $\gamma$-ray fluxes from the long campaigns on Mrk421 as constraints on the emission of TeV-PeV Neutrinos and UHECRs
• Could a plasma in quasi-thermal equilibrium be associated to the "orphan" TeV flares ?
• Search for Global Dipole Enhancements in the HiRes-I Monocular Data above 10^{18.5} eV
• Search for single sources of ultra high energy cosmic rays on the sky
• Impact of using the ultra-high-energy cosmic ray arrival energies to constrain source associations
• On the excess of ultra-high energy cosmic rays in the direction of Centaurus A
• Ultra High Energy Cosmic Rays & Super-heavy Dark Matter
• Galactic Magnetic Field Bias on Inferences from UHECR Data
• Ultra high energy cosmic rays from super-heavy dark matter in the context of large exposure observatories
• Detecting ultra-high energy cosmic ray anisotropies through cross-correlations
• Measurements and implications of cosmic ray anisotropies from TeV to trans-EeV energies
• Anisotropies of Ultra-high Energy Cosmic Rays Dominated by a Single Source in the Presence of Deflections
• Sensitivity of full-sky experiments to large scale cosmic ray anisotropies
• Testing the isotropy of high energy cosmic rays using spherical needlets
• A new method to search for a cosmic ray dipole anisotropy
• On the Measurement of the Helicity of Intergalactic Magnetic Fields Using Ultra-High-Energy Cosmic Rays
• On the Contribution of Unresolved Pulsars to the Ultra-high-energy Galactic Diffuse Gamma-Ray Emission
• Search for point sources of ultra-high energy photons with the Telescope Array surface detector
• The Fortuitous Latitude of the Pierre Auger Observatory and Telescope Array for Reconstructing the Quadrupole Moment
• Detecting filaments in the ultra-high energy cosmic ray distribution
• Observation of Cosmic-Ray Anisotropy in the Southern Hemisphere with 12 yr of Data Collected by the IceCube Neutrino Observatory
• IceCube expectations for two high-energy neutrino production models at active galactic nuclei
• Statistics of cluster multiplicity and the nature of UHE cosmic ray sources
• Ultra High Energy Cosmic Rays: Anisotropies and Spectrum
• Small Scale Anisotropy Predictions for the Auger Observatory
• Systematic Survey of the Correlation between Northern HECR Events and SDSS Galaxies
• Astrophysical interpretation of the medium scale clustering in the ultra-high energy sky
• Studies of the UHECR propagation in the Galactic Magnetic Field
• Treasure Maps for Detections of Extreme Energy Cosmic Rays
• Revisit of Correlation Analysis between Active Galactic Nuclei and Ultra-High Energy Cosmic Rays
• Multiscale autocorrelation function: a new approach to anisotropy studies
• A coverage independent method to analyze large scale anisotropies
• The distribution of ultra-high-energy cosmic rays along the supergalactic plane measured at the Pierre Auger Observatory
• Prospects of detecting a large-scale anisotropy of ultra-high-energy cosmic rays from a nearby source with the K-EUSO orbital telescope
• Declination dependence of the cosmic-ray flux at extreme energies
• A Heavy-Metal Scenario of Ultra-High-Energy Cosmic Rays
• Bounds from multi-messenger astronomy on the Super Heavy Dark Matter
• Constraining ultra-high-energy cosmic ray composition through cross-correlations
• Modelling cross-correlations of ultra-high-energy cosmic rays and galaxies
• Sensitivity of orbiting JEM-EUSO to large-scale cosmic-ray anisotropies
• On the Global Anisotropy of Cosmic Ray Data above $4\times 10^{19}eV$
• 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
• Effects of galactic magnetic field on the UHECR correlation studies with starburst galaxies
• On Estimating the Flux of the Brightest Cosmic Ray Source above 57x10^18 eV
• Techniques to study cosmic ray anisotropies
• Correlation between Ultra-high Energy Cosmic Rays and Active Galactic Nuclei from Fermi Large Area Telescope
• Large-scale anisotropies of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory
• Anisotropy studies with multiscale autocorrelation function
• Towards extracting cosmic magnetic field structures from cosmic-ray arrival directions
• The influence of the observatory latitude on the study of ultra high energy cosmic rays