Abstract
Ultrahigh-energy cosmic rays (UHECRs) are known to come from outside of our Galaxy, but their origin still remains unknown. The Telescope Array (TA) experiment recently identified a hotspot, that is, a high concentration of anisotropic arrival directions of UHECRs with energies above 5.7 Å ~ 1019 eV. We report here the presence of filaments of galaxies, connected to the Virgo Cluster, in the sky around the hotspot and a statistically significant correlation between hotspot events and the filaments. With 5-year TA data, the maximum significance of binomial statistics for the correlation is estimated to be 6.1σ at correlation angle 3.4°. The probability that the above significance appears by chance is ~2.0 × 10-8 (5.6σ). On the basis of this finding, we suggest a model for the origin of TA hotspot UHECRs; they are produced at sources in the Virgo Cluster, and escape to and propagate along filaments, before they are scattered toward us. This picture requires the filament magnetic fields of strength ≳ 20 nG, which need to be confirmed in future observations.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
