GZK horizon and magnetic fields
نویسندگان
چکیده
منابع مشابه
GZK horizon and magnetic fields
We discuss some aspects of the propagation of high-energy cosmic rays (CRs) in turbulent magnetic fields, and propose a formula for the diffusion coefficient based on accurate simulations in a wide energy range. We discuss the transition between ballistic and diffusive regimes and the magnetic horizon of CR sources, showing how magnetic fields of a few nG could modify the shape of the GZK featu...
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We discuss the GZK horizon of protons and present a method to constrain the injection spectrum of ultrahigh energy cosmic rays (UHECRs) from supposedly identified extragalactic sources. This method can be applied even when only one or two events per source are observed and is based on the analysis of the probability for a given source to populate different energy bins, depending on the actual C...
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We study the effect of random extra-galactic magnetic fields on the propagation of protons of energy larger than 10 eV. We show that for reasonable field values (in the 100 nG range) the transition between diffusive and ballistic regimes occurs in the same energy range as the GZK cutoff (a few 10 eV). The usual interpretation of the flux reduction above the GZK energy in terms of a sudden reduc...
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Magnetic fields are considered to be dominant when εB ≥ εK , being εB = B /8π the magnetic energy density and εK = 1/2ρθ 2 the rotation energy density, for a conventional moderate B= 1 μG. They are considered to be negligible when εB < εK for B ∼ 10μG. With no assumption and no theoretical calculation, we show that magnetic fields cannot be ignored in the outer parts of a galaxy like the Milky ...
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ژورنال
عنوان ژورنال: Nuclear Physics B - Proceedings Supplements
سال: 2004
ISSN: 0920-5632
DOI: 10.1016/j.nuclphysbps.2004.10.034