Título
Interactions, star formation and extended nebulae in SDSS type 2 quasars at 0.3 ≲ z ≲ 0.6 🟉
Autor
Andrew Humphrey
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
We present long-slit spectroscopy and imaging data obtained with the Focal Reducer and Low Dispersion Spectrograph (FORS2) on the Very Large Telescope of 13 optically selected type 2 quasars at z ∼ 0.3–0.6 from the original sample of Zakamska et al. (2003). The sample is likely to be affected by different selection biases.We investigate the evidence for (i) mergers/interactions (ii) star formation activity in the neighbourhood of the quasars and (iii)
extended emission-line regions (EELRs) and their nature. Evidence for mergers/interactions is found in 5/13 objects. This is a lower limit for our sample, given the shallowness ofmost of our continuum images. Although active galactic nucleus (AGN) photoionization cannot be totally discarded, line ratios consistent with stellar photoionization are found in general in companion galaxies/knots/nuclei near these same objects. On the contrary, the gas in the neighbourhood of the quasar nucleus shows line ratios inconsistent with HII galaxies and typical of AGN photoionized nebulae. A natural scenario to explain the observations is that star formation is ongoing in companion galaxies/knots/nuclei, possibly triggered by the interactions. These systems are, therefore, composite in their emission-line properties showing a combination of AGN and star formation features. EELRs have been found in 7/13 objects, although this fraction might be higher if a complete spatial coverage around the quasars was performed. The sizes vary between a few and up to 64 kpc. In general, the EELR apparently consists of an extended nebula associated with the quasar. In at least one case, the EELR is associated with ionized tidal features.
Editor
Monthly Notices of the Royal Astronomical Society
Fecha de publicación
2011
Tipo de publicación
Artículo
Versión de la publicación
Versión aceptada
Recurso de información
Formato
application/pdf
Idioma
Inglés
Relación
, Monthly Notices of the Royal Astronomical Society, Vol. 416(1): 262–278
Audiencia
Estudiantes
Investigadores
Público en general
Sugerencia de citación
Villar Martín, M., et al., (2011), Interactions, star formation and extended nebulae in SDSS type 2 quasars at 0.3 ≲ z ≲ 0.6 🟉
Repositorio Orígen
Repositorio Institucional del INAOE
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