Limit on the intergalactic magnetic field from the ultrahigh-energy cosmic ray hotspot in the Perseus-Pisces region
The Telescope Array Collaboration has reported an evidence for existence of a source of ultrahigh energy cosmic ray events in Perseus-Pisces supercluster. We show that the mere existence of such a source imposes an upper bound on the strength of intergalactic magnetic field (IGMF) in the Taurus void lying between the Perseus-Pisces supercluster and the Milky Way galaxy. This limit is at the level of 10-10 G for a field with correlation length larger than the distance of the supercluster (similar to 70 Mpc). This bound is an order-of-magnitude stronger that the previously known bound on IGMF from radio Faraday rotation measurements and it is the first upper bound on magnetic field in the voids of the large-scale tructure. Our analysis indicates that the source has to be dominated by protons, because heavier nuclei are either photodisintegrated or are too strongly deflected by the Galactic magnetic field.
WOS:001117674900002
2023-11-08
108
10
103008
REVIEWED
EPFL
Funder | Grant Number |
French National Research Agency (ANR) | ANR-19-CE31-0020 |
Ministry of Science and Higher Education of the Russian Federation | 075-15-2020-778 |