Bibcode
Domínguez, A.; Sánchez-Conde, M. A.; Prada, F.
Referencia bibliográfica
Journal of Cosmology and Astroparticle Physics, Issue 11, pp. 020 (2011).
Fecha de publicación:
11
2011
Número de citas
61
Número de citas referidas
52
Descripción
Discoveries of very high energy (VHE) photons from distant blazars
suggest that, after correction by extragalactic background light (EBL)
absorption, there is a flatness or even a turn-up in their spectra at
the highest energies that cannot be easily explained by the standard
framework. Here, it is shown that a possible solution to this problem is
achieved by assuming the existence of axion-like particles (ALPs) with
masses ~ 1 neV. The ALP scenario is tested making use of observations of
the highest redshift blazars known in the VHE energy regime, namely 3C
279, 3C 66A, PKS 1222+216 and PG 1553+113. In all cases, better fits to
the observed spectra are found when including ALPs rather than
considering EBL only. Interestingly, quite similar critical energies for
photon/ALP conversions are also derived, independently of the source
considered.