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arXiv · 1412.3171

Intergalactic magnetic field spectra from diffuse gamma rays

Wenlei Chen·Borun D. Chowdhury·Francesc Ferrer·Hiroyuki Tashiro·Tanmay Vachaspati
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Abstract

Non-vanishing parity-odd correlators of gamma ray arrival directions observed by Fermi-LAT indicate the existence of a helical intergalactic magnetic field (Tashiro et al.2013). We successfully test this hypothesis using more stringent cuts of the data, Monte Carlo simulations with Fermi-LAT time exposure information, separate analyses for the northern and southern galactic hemispheres, and confirm predictions made in Tashiro & Vachaspati (2014). With some further technical assumptions, we show how to reconstruct the magnetic helicity spectrum from the parity-odd correlators.

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Wenlei Chen, Borun D. Chowdhury, Francesc Ferrer, Hiroyuki Tashiro, Tanmay Vachaspati. 2014-12-10. Intergalactic magnetic field spectra from diffuse gamma rays. https://doi.org/10.1093/mnras%2Fstv308

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