On the nature of the near-UV extended light in Seyfert galaxies

• Autor(a) principal: Muñoz Marín, Victor M.
• Data de Publicação: 2009
• Outros Autores: Storchi-Bergmann, Thaisa, González Delgado, Rosa M., Schmitt, Henrique Roberto, Spinelli, Patrícia Figueiro, Pérez Jiménez, Enrique, Fernandes Junior, Roberto Cid
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/90457
• topic: Nucleo galatico; Galaxias seyfert; Galáxias ativas; Polarimetria; Espectroscopia otica; Galaxies: nuclei; Galaxies: Seyfert; Ultraviolet: galaxies

We study the nature of the extended near-UV emission in the inner kiloparsec of a sample of 15 Seyfert (Sy) galaxies which have both near-UV (F330W) and narrow-band [O III] highresolution Hubble images. For the majority of the objects, we find a very similar morphology in both bands. From the [O III] images, we construct synthetic images of the nebular continuum plus the emission-line contribution expected through the F330W filter, which can be subtracted from the F330W images. We find that the emission of the ionized gas dominates the near-UV extended emission in half of the objects. A further broad-band photometric study, in the bands F330W (U), F547M (V) and F160W (H), shows that the remaining emission is dominated by the underlying galactic bulge contribution. We also find a blue component whose nature is not clear in four out of 15 objects. This component may be attributed to scattered light from the active galactic nuclei, to a young stellar population in unresolved star clusters, or to early disrupted clusters. Star-forming regions and/or bright off nuclear star clusters are observed in 4/15 galaxies of the sample.