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arXiv · 1001.2171

A New Light Boson from Cherenkov Telescopes Observations?

Marco Roncadelli·Alessandro De Angelis·Oriana Mansutti
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Abstract

Early indications by H.E.S.S. and the subsequent detection of blazar 3C279 by MAGIC show that the Universe is more transparent to very-high-energy gamma rays than previously thought. We demonstrate that this circumstance can be reconciled with standard blazar emission models provided that photon oscillations into a very light Axion-Like Particle occur in extragalactic magnetic fields. A quantitative estimate of this effect indeed explains the observed spectrum of 3C279. Our prediction can be tested by the satellite-borne Fermi/LAT detector as well as by the ground-based Imaging Atmospheric Cherenkov Telescopes H.E.S.S., MAGIC, CANGAROO III, VERITAS and by the Extensive Air Shower arrays ARGO-YBJ and MILAGRO.

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Marco Roncadelli, Alessandro De Angelis, Oriana Mansutti. 2010-01-13. A New Light Boson from Cherenkov Telescopes Observations?. https://arxiv.org/abs/1001.2171

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