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arXiv · 0907.3192

Region of Excessive Flux of PeV Cosmic Rays in the Direction Toward Pulsars PSR J1840+5640 and LAT PSR J1836+5925

G. V. Kulikov·M. Yu. Zotov
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Abstract

An analysis of arrival directions of extensive air showers (EAS) registered with the EAS MSU and EAS-1000 prototype arrays has revealed a region of excessive flux of PeV cosmic rays in the direction toward pulsars PSR J1840+5640 and LAT PSR J1836+5925 at significance level up to 4.5sigma. The first of the pulsars was discovered almost 30 years ago and is a well-studied old radio pulsar located at the distance of 1.7pc from the Solar system. The second pulsar belongs to a new type of pulsars, discovered by the space gamma-ray observatory Fermi, pulsations of which are not observed in optical and radio wavelengths but only in the gamma-ray range of energies (gamma-ray-only pulsars). In our opinion, the existence of the region of excessive flux of cosmic rays registered with two different arrays provides a strong evidence that isolated pulsars can give a noticeable contribution to the flux of Galactic cosmic rays in the PeV energy range.

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G. V. Kulikov, M. Yu. Zotov. 2009-07-19. Region of Excessive Flux of PeV Cosmic Rays in the Direction Toward Pulsars PSR J1840+5640 and LAT PSR J1836+5925. https://doi.org/10.1134/s1063773710090033

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