Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Abstract

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.

arXiv commentMatches published version

References in corpus (16)

• Discovery of Very-High-Energy Gamma-Rays from the Galactic Centre Ridge
• Very high energy gamma rays from the direction of Sagittarius A*
• Calibration of cameras of the H.E.S.S. detector
• The Anisotropy of Cosmic Ray Arrival Direction around 10^18eV
• The Anisotropy of Cosmic Ray Arrival Directions around 10${}^{18}$eV
• High energy gamma rays from the massive black hole in the Galactic Center
• Southern Hemisphere Observations of a $10^{18}$eV Cosmic Ray Source Near the Direction of the Galactic Centre
• The AGASA/SUGAR Anisotropies and TeV Gamma Rays from the Galactic Center: A Possible Signature of Extremely High-energy Neutrons
• The last Gamma Ray Burst in our Galaxy? On the observed cosmic ray excess at particle energy 1 EeV
• First Estimate of the Primary Cosmic Ray Energy Spectrum above 3 EeV from the Pierre Auger Observatory
• Sgr A East as a possible high energy neutron factory in the Galactic Centre
• Decaying neutron propagation in the Galaxy and the Cosmic Ray anisotropy at 1 EeV
• Aperture calculation of the Pierre Auger Observatory surface detector
• Coverage and large scale anisotropies estimation methods for the Pierre Auger Observatory
• Fitting the HiRes Spectra
• A procedure to produce excess, probability and significance maps and to compute point-sources flux upper limits

Cited by in corpus (31)

• Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei
• Cosmic Rays from the Knee to the Highest Energies
• Influence of hadronic interaction models and the cosmic ray spectrum on the high energy atmospheric muon and neutrino flux
• A Search for Point Sources of EeV Neutrons
• Faraday rotation, stochastic magnetic fields and CMB maps
• Cosmic Rays: The Second Knee and Beyond
• Magnetogenesis, spectator fields and CMB signatures
• Cosmic Ray Astronomy
• LUNASKA Experiment Observational Limits on UHE Neutrinos from Centaurus A and the Galactic Center
• Measurement of the Aerosol Phase Function at the Pierre Auger Observatory
• Electric-magnetic duality and the conditions of inflationary magnetogenesis
• Generalized CMB initial conditions with pre-equality magnetic fields
• A magnetized completion of the $\Lambda$CDM paradigm
• Super Heavy Dark Matter and UHECR Anisotropy at Low Energy
• A Targeted Search for Point Sources of EeV Neutrons
• Probing large-scale magnetism with the Cosmic Microwave Background
• Distortion of the ultrahigh energy cosmic ray flux from rare transient sources in inhomogeneous extragalactic magnetic fields
• A global autocorrelation study after the first Auger data: impact on the number density of UHECR sources
• A Bayesian analysis of the 27 highest energy cosmic rays detected by the Pierre Auger Observatory
• First results from the Pierre Auger Observatory
• Significance in Gamma Ray Astronomy with Systematic Errors
• Recent results from the Pierre Auger Observatory
• Bootstrapping from inflationary magnetogenesis to CMB initial conditions
• The Pierre Auger Observatory: Results on Ultra-High Energy Cosmic Rays
• The Pierre Auger Cosmic Ray Observatory, Comments on Recent Results
• Estimating a cosmic ray detector exposure sky map under the hypothesis of seasonal and diurnal effects factorization
• On Integral Upper Limits Assuming Power Law Spectra and the Sensitivity in High-Energy Astronomy
• Techniques to study cosmic ray anisotropies
• Are EeV cosmic rays isotropic at intermediate scales?
• Physics Results of the Pierre Auger Observatory
• Anisotropy Studies with the Pierre Auger Observatory