%0 Journal Article
%T Probing axion-like particles with the ultraviolet photon polarization from active galactic nuclei in radio galaxies
%A D. Horns
%A L. Maccione
%A A. Mirizzi
%A M. Roncadelli
%J Physics
%D 2012
%I arXiv
%R 10.1103/PhysRevD.85.085021
%X The mixing of photons with axion-like particles (ALPs) in the large-scale magnetic field $B$ changes the polarization angle of a linearly polarized photon beam from active galactic nuclei in radio galaxies as it propagates over cosmological distances. Using available ultraviolet polarization data concerning these sources we derive a new bound on the product of the photon-ALP coupling $g_{a\gamma}$ times $B$. We find $g_{a\gamma} B \lesssim 10^{-11}$ GeV$^{-1}$ nG for ultralight ALPs with $m_a \lesssim 10^{-15}$ eV. We compare our new bound with the ones present in the literature and we comment about possible improvements with observations of more sources.
%U http://arxiv.org/abs/1203.2184v2