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arXiv · astro-ph/0412410

Asymmetrical structure of ionization and kinematics in the Seyfert galaxy NGC 5033

E. Mediavilla·A. Guijarro·A. Castillo-Morales·J. Jimenez-Vicente·E. Florido·S. Arribas·B. Garcia-Lorenzo·E. Battaner
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Abstract

We present integral field spectroscopy of NGC 5033, a low luminosity Seyfert galaxy. The observations were made with INTEGRAL, a fiber based system operating at the WHT. The intensity map of the H$β$ emission line represents a spiral or ring-like pattern of HII regions. On the contrary, the [OIII] intensity map morphology is markedly anisotropic. The strong morphological differences imply that the [OIII] emitters represent highly ionized gas illuminated by the central source. The [OIII] map morphology is compatible with a biconical structure of ionization induced by strong extinction in the galaxy disc that also obscures half of the spheroidal stellar bulge. We identify the spectrum corresponding to the Seyfert 1 nucleus from the presence of H$β$ broad emission lines. This spectrum is located in a region where strong extinction is expected but exhibits the bluest spectral energy distribution. The Seyfert 1 nucleus seems to be offcenter with respect to the stellar rotation center. This result has been also found in other Seyfert galaxies and interpreted in terms of a past merger. The offcentering could indicate the presence of nonsymmetric departures in the gravitational potential which could be fueling the active nucleus. The kinematics of the [OIII] emitters show important deviations at a kpc scale with respect to the stellar velocity field and show features related to the asymmetrical morphology of the high ionization region.

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E. Mediavilla, A. Guijarro, A. Castillo-Morales, J. Jimenez-Vicente, E. Florido, S. Arribas, B. Garcia-Lorenzo, E. Battaner. 2004-12-16. Asymmetrical structure of ionization and kinematics in the Seyfert galaxy NGC 5033. https://doi.org/10.1051/0004-6361%3A20034537

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