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

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 Hβ emission line represents a spiral or ring-like pattern of HII regions. On the contrary, the [OIII] int...

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Detalles Bibliográficos
Autores: Mediavilla, E., Guijarro, A., Castillo-Morales, A., Jiménez-Vicente, J., Florido, E., Arribas-Mocoroa, Santiago, García-Lorenzo, B., Battaner, E.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/199137
Acceso en línea:http://hdl.handle.net/10261/199137
Access Level:acceso abierto
Palabra clave:Galaxies: active
Galaxies: individual: NGC 5033
Galaxies: kinematics and dynamics
Galaxies: spiral
Galaxies: seyfert
Galaxies: nuclei
Descripción
Sumario: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 Hβ 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 [OUI] 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 Hβ 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.