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IMAGING SPECTROPHOTOMETRY OF MARKARIAN 573

Richard Pogge·Michael De Robertis
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Abstract

Narrow-band emission-line and continuum images obtained in subarcsecond seeing conditions are presented for the Seyfert~2 galaxy, Markarian 573. Images in the emission-lines of [\oi], [\oii], [\oiii], [\sii], and \halpha+[\nii] are used to measure the structure and excitation in the extended emission regions surrounding the active nucleus. The biconical region contains a variety of complex features, including two arc-like structures within $\sim 2\arcsec$ of the active nucleus that appear to be associated with the extended radio continuum emission in the sense that the radio lobes lie just inside the centroids of the emission-line arcs. These arcs probably arise from an interaction between the ISM and the radio plasma from the active nucleus. Two other emission-line features lie $\sim3-4\arcsec$ on either side of the nucleus, and appear to be elongated nearly perpendicular to the symmetry axis of the inner radio and optical structures. The existence of multiple emission-line components could be evidence for episodic ejection of radio plasma from the active nucleus.

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Richard Pogge, Michael De Robertis. 1995-06-03. IMAGING SPECTROPHOTOMETRY OF MARKARIAN 573. https://doi.org/10.1086/176246

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