arXiv:0911.1056·v1·Cosmology and Nongalactic Astrophysics
Detection of distant AGN by MAGIC: the transparency of the Universe to high-energy photons
Marco Roncadelli (1) · Alessandro De Angelis (2) · Oriana Mansutti (3) ((1) INFN, Sezione di Pavia, Italy, (2) Dipartimento di Fisica, Universita' di Udine, and INAF and INFN, Sezioni di Trieste, Italy, (3) Dipartimento di Fisica, Universita' di Udine, and INFN, Sezione di Trieste, Italy)
Abstract
The recent detection of blazar 3C279 by MAGIC has confirmed previous indications by H.E.S.S. that the Universe is more transparent to very-high-energy gamma rays than previously thought. We show that this fact can be reconciled with standard blazar emission models provided photon oscillations into a veri light Axion-Like Particle occur in extragalactic magnetic fields. A quantitative estimate of this effect explains the observed spectrum of 3C279. Our prediction can be tested in the near future by the satellite-borne GLAST detector as well as by the ground-based Imaging Atmospheric Cherenkov Telescpoes H.E.S.S., MAGIC, CANGAROO III, VERITAS and by the Extensive Air Shower arrays ARGO-YBJ and MILAGRO.
Comments: 4 pages, 1 figure, Proceeding of the Conference "4th Patras Workshop on Axions, WIMPs and WISPs"