At a distance of 20 pc from the purported supermassive black hole powering quasars, temperatures and densities are inferred from optical observations to be ~10**4 K and ~10**4 cm**-3. Here we present Very Long Baseline Interferometry radio observations revealing organized magnetic fields on the parsec scale in the hot plasma surrounding the quasar OQ172 (1442+101). These magnetic fields rotate the plane of polarization of the radio emission coming from the core and inner jet of the quasar. The derived rotation measure (RM) is 40,000 rad m**-2 in the rest frame of the quasar. Only 10 mas (a projected distance of 68 pc) from the nucleus the jet absolute values of RM fall to less than 100 rad m**-2.
@article{arxiv.astro-ph/9704112,
title = {Evidence for Ordered Magnetic Fields in the Quasar Environment},
author = {P. S. Udomprasert and G. B. Taylor and T. J. Pearson and D. H. Roberts},
journal= {arXiv preprint arXiv:astro-ph/9704112},
year = {2009}
}
Comments
in press at ApJ Letters, 12 page LaTeX document includes 4 postscript figures