The Anisotropy of Cosmic Ray Arrival Directions around 10eV
نویسندگان
چکیده
Anisotropy in the arrival directions of cosmic rays with energies above 10eV is studied using data from the Akeno 20 km array and the Akeno Giant Air Shower Array (AGASA), using a total of about 114,000 showers observed over 11 years. In the first harmonic analysis, we have found strong anisotropy of ∼ 4% around 10eV, corresponding to a chance probability of ∼ 0.2% after taking the number of independent trials into account. With two dimensional analysis in right ascension and declination, this anisotropy is interpreted as an excess of showers near the directions of the Galactic Center and the Cygnus region.
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