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NUclei of GAlaxies: V. Radio emission in 7 NUGA sources

M. Krips·A. Eckart·T. P. Krichbaum·J. -U. Pott·S. Leon·R. Neri·S. Garcia-Burillo·F. Combes·F. Boone·A. J. Baker·L. J. Tacconi·E. Schinnerer·L. K. Hunt
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Abstract

We present high angular resolution radio snap-shot observations of seven nearby low-luminosity active galaxies (LLAGN) from the NUclei of GAlaxies (NUGA) survey. The observations were conducted with MERLIN and EVN/VLBI at 18cm and 6cm. At all observed angular resolutions and frequencies, we find indications for extended emission in about ~40% of the sources, consistent with the decrease of flux with increasing angular resolution. The extended components resemble jet emission in a majority of cases, consistent with the optically thin synchrotron emission implied by their steep spectra. We consider the compact 6cm EVN/VLBI radio emission of our sources in the context of the ``fundamental plane'' that previous LLAGN studies identified within the three-dimensional parameter space of radio luminosity, X-ray luminosity, and black hole mass. We demonstrate, using NGC7217 and NGC1068 as particular examples, that high-resolution, multi-epoch radio observations offer useful information about the origin of offsets from the fundamental plane.

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M. Krips, A. Eckart, T. P. Krichbaum, J. -U. Pott, S. Leon, R. Neri, S. Garcia-Burillo, F. Combes, F. Boone, A. J. Baker, L. J. Tacconi, E. Schinnerer, L. K. Hunt. 2007-01-02. NUclei of GAlaxies: V. Radio emission in 7 NUGA sources. https://doi.org/10.1051/0004-6361%3A20065037

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