Título
Ionized outflows in SDSS type 2 quasars at z ∼ 0.3–0.6🟉
Autor
Andrew Humphrey
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
We have analysed the spatially integrated kinematic properties of the ionized gas within the inner r ≲ few kpc in 13 optically selected SDSS type 2 quasars at z ∼ 0.3–0.6, using the [O 🇮🇮🇮]λλ4959,5007 lines. The line profiles show a significant asymmetry in 11 objects. There is a clear preference for blue asymmetries, which are found in 9/13 quasars at 10 per cent intensity level. In coherence with studies on other types of active and non active galaxies, we propose that the asymmetries are produced by outflows where differential dust extinction is at work. This scenario is favoured by other results we find: in addition to quiescent ambient gas, whose kinematic properties are consistent with gravitational motions, we have discovered highly perturbed gas in all objects. This gas emits very broad lines (R = FWHM[O 🇮🇮🇮]/FWHMstars ≳2).While the quiescent gas shows small or null velocity shifts relative to the systemic velocity, the highly perturbed gas trends to show larger shifts which, moreover, are blueshifts in general. Within a given object, the most perturbed gas trends to have the largest blueshift as well. All together support that the perturbed gas, which is responsible for the blue asymmetries of the line profiles, is outflowing. The outflowing gas is located within the quasar ionization cones, in the narrow line region. The relative contribution of the outflowing gas to the total [O 🇮🇮🇮] line flux varies from object to object in the range ∼10–70 per cent. An anticorrelation is found such that, the more perturbed the outflowing gas is, the lower its relative contribution is to the total [O 🇮🇮🇮] flux. This suggests that outflows with more perturbed kinematics involve a smaller fraction of the total mass of ionized gas. Although some bias affects the sample, we argue that ionized gas outflows are a common phenomenon in optically selected type 2 quasars at 0.3≲ z ≲ 0.6.
Editor
Monthly Notices of the Royal Astronomical Society
Fecha de publicación
diciembre de 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.418(13):2032–2042
Audiencia
Estudiantes
Investigadores
Público en general
Sugerencia de citación
Villar Martín, M., et al., (2011), Ionized outflows in SDSS type 2 quasars at z ∼ 0.3–0.6 🟉
Repositorio Orígen
Repositorio Institucional del INAOE
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