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arXiv · 1407.1583

Large-scale distribution of cosmic rays in right ascension as observed by the Yakutsk array at energies above $10^{18}$ eV

A. A. Ivanov·A. D. Krasilnikov·M. I. Pravdin·A. V. Sabourov
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Abstract

We present the results of searches for anisotropy in the right ascension ($RA$) distribution of arrival directions of cosmic rays (CRs) detected with the Yakutsk array during the 1974--2008 observational period in the energy range above $10^{18}$ eV. Two methods of analysis are applied to two sub-samples of the data. Particularly, estimations of the first and second harmonic amplitudes are given, as well as the first harmonic phase in adjacent energy intervals. Analysis of variance demonstrates a significant contraction of the minimal width of the $RA$ distribution in the energy bin $(10^{19},1.78\times10^{19})$ eV with respect to the isotropic distribution, which may be attributed to a possible source of CRs within the interval $RA\in(15^0,45^0)$.

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A. A. Ivanov, A. D. Krasilnikov, M. I. Pravdin, A. V. Sabourov. 2014-07-07. Large-scale distribution of cosmic rays in right ascension as observed by the Yakutsk array at energies above $10^{18}$ eV. https://doi.org/10.1016/j.astropartphys.2014.07.002

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