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Magnetic Fields in AGN

Published online by Cambridge University Press:  12 April 2016

J. F. C. Wardle*
Affiliation:
Physics Department, Brandeis University, Waltham, MA 02254, U.S.A.

Abstract

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We review VLBI polarization results. In particular, we discuss the a) “shock in jet paradigm”, b) the orientation of the magnetic field in jets as a function of optical identification, c) rotation measure and Faraday dispersion measurements as a probe of the narrow line region, and d) future directions of polarization observations. Results we emphasize are i) there is still a strong correlation between optical L/C ratio or EW and magnetic field orientation in the jets of blazars, even for high redshift weak-lined objects, ii) observed rotation measures are much smaller than expected from the properties of the NLR, except for some CSS sources. Also iii) a faint boundary layer or sheath (with a parallel magnetic field) has been observed around the jet of the weak-lined blazar 1055+018, and iv) circular polarization has been detected for the first time in the jets of 3C 84 and 3C 279.

Type
Research Article
Copyright
Copyright © Astronomical Society of the Pacific 1998

References

Antonucci, R.R.J. 1993. ARA&A, 31, 473521.Google Scholar
Blandford, R.D., & Königl, A. 1979. ApJ, 232, 3448.Google Scholar
Cawthorne, T.V., et al. 1993. ApJ, 416, 519535.Google Scholar
Fanti, R., et al. 1990. A&A, 231, 333346.Google Scholar
Gabuzda, D.C., et al. 1994. ApJ, 435, 140161.Google Scholar
Hughes, P.A., Aller, H.D., & Aller, M.H. 1985. ApJ, 298, 301315.Google Scholar
Jones, T.W., & O’Dell, S.L. 1977. ApJ, 214, 522539.Google Scholar
Jones, T.W. 1988. ApJ, 332, 678695.Google Scholar
Kühr, H., & Schmidt, G.D. 1990. AJ, 99, 16.Google Scholar
Laing, R.A. 1996. In Energy Transport in Radio Galaxies and Quasars, eds. Hardee, P.E., Bridle, A.H., & Zensus, J.A. (San Fransico: ASP), 241252.Google Scholar
Leppänen, K.J., Zensus, J.A., & Diamond, P.J. 1995. AJ, 110, 24792492.Google Scholar
Marscher, A.P., & Gear, W.K. 1985. ApJ, 298, 114127.Google Scholar
O’Dea, C.P. 1989. A&A, 210, 3541.Google Scholar
Osterbrock, D.E. 1993. ApJ, 404, 551562.Google Scholar
Pearson, T.J., & Readhead, A.C.S. 1988. ApJ, 328, 114142.Google Scholar
Rees, M.J. 1987. MNRAS, 228, 47P50P.Google Scholar
Rudnick, L., & Jones, T.W. 1983. AJ, 88, 518526.Google Scholar
Wardle, J.F.C., et al. 1994. ApJ, 437, 122135.Google Scholar
Wardle, J.F.C., et al. 1996. In Millimeter-VLBI Science Workshop, eds. Barvainis, R. & Phillips, R.B. (Cambridge: MIT), 6367.Google Scholar