GZK Violation – a Tempest in a (Magnetic) Teapot?
نویسندگان
چکیده
Faraday rotation measurements are used to constrain simple models representing possible extremes of the structure of extra-galactic magnetic fields (EGMFs). Relevant fields are found quite generally to be at the μG level rather than the nG level usually assumed. Even the highest energy cosmic ray protons should experience large deflections over distances of order 1 Mpc. Such large deflections allow either GRBs or AGNs to be the source of ultrahigh energy cosmic rays, with AGNs tolerating greater inefficiency in the cosmic ray acceleration mechanism. \pacs{} Typeset using REVTEX
منابع مشابه
Violation of the Greisen-Zatsepin-Kuzmin cutoff: a tempest in a (magnetic) Teapot? Why cosmic ray energies above 10(20) eV may not require new physics.
The apparent lack of suitable astrophysical sources for the observed highest energy cosmic rays within approximately 20 Mpc is the "Greisen-Zatsepin-Kuzmin (GZK) paradox." We constrain representative models of the extragalactic magnetic field structure by Faraday rotation measurements; limits are at the microG level rather than the nG level usually assumed. In such fields, even the highest ener...
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