Year: 2014
Type: article
Abstract: Although it is well known that massive galaxies have central black holes, most of them accreting at low Eddington ratios, many important questions still remain open.Among them are the nature of the ionizing source, the characteristics and frequencies of the broad-line region and of the dusty torus.We report observations of 10 early-type galactic nuclei, observed with the Gemini Multi Object Spectrograph in integral field unit mode, installed on the Gemini South telescope, analysed with standard techniques for spectral treatment and compared with results obtained with principal component analysis Tomography (Paper I).We performed spectral synthesis of each spaxel of the data cubes and subtracted the stellar component from the original cube, leaving a data cube with emission lines only.The emission lines were decomposed in multi-Gaussian components.We show here that, for eight galaxies previously known to have emission lines, the narrow-line region can be decomposed in two components with distinct line widths.In addition to this, broad Hα emission was detected in six galaxies.The two galaxies not previously known to have emission lines show weak Hα+[N II] lines.All 10 galaxies may be classified as low-ionization nuclear emission regions in diagnostic diagrams and seven of them have bona fide active galactic nuclei with luminosities between 10 40 and 10 43 erg s -1 .Eddington ratios are always <10 -3 .
DOI: 10.1093/mnras/stu442
Authors: T. V. Ricci, J. E. Steiner, R. B. Menezes
Institution: Universidade de São Paulo
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W1985040331