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arXiv · 2008.06279

Searching for primordial helical magnetic fields

M. Kachelriess·B. C. Martinez
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Abstract

The presence of non-zero helicity in intergalactic magnetic fields (IGMF) has been suggested as a clear signature for their primordial origin. We extend a previous analysis of diffuse Fermi-LAT gamma-ray data from 2.5 to more than 11 years and show that a hint for helical magnetic fields in the 2.5 year data was a statistical fluctuation. Then we examine the detection prospects of helical magnetic fields using individual sources as, e.g., TeV gamma-ray blazars. We find that a detection is challenging employing realistic models for the cascade evolution, the IGMF and the detector resolution in our simulations.

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M. Kachelriess, B. C. Martinez. 2020-08-14. Searching for primordial helical magnetic fields. https://doi.org/10.1103/physrevd.102.083001

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