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Title: The Large-scale Anisotropy and Flux (de)magnification of Ultrahigh-energy Cosmic Rays in the Galactic Magnetic Field
Abstract We calculate the arrival direction distribution of ultrahigh-energy cosmic rays (UHECRs) with a new suite of models of the Galactic magnetic field (GMF), assuming sources follow the large-scale structure of the Universe. Compared to previous GMF models, the amplitude of the dipole component of the UHECR arrival flux is significantly reduced. We find that the reduction is due to the accidentally coinciding position of the peak of the extragalactic UHECR flux and the boundary of strong flux demagnification due to the GMF toward the central region of the Galaxy. This serendipitous sensitivity of UHECR anisotropies to the GMF model will be a powerful probe of the source distribution as well as Galactic and extragalactic magnetic fields. Demagnification by the GMF also impacts the visibility of some popular source candidates.  more » « less
Award ID(s):
2013199
PAR ID:
10559024
Author(s) / Creator(s):
; ;
Publisher / Repository:
AAS
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
975
Issue:
1
ISSN:
2041-8205
Page Range / eLocation ID:
L21
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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