Related papers: Where is the coronal line region in active galacti…
We present Gemini/GNIRS spectroscopy of the Seyfert 2 galaxy NGC 4388, with simultaneous coverage from 0.85 - 2.5 $\mu$m. Several spatially-extended emission lines are detected for the first time, both in the obscured and unobscured portion…
We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modelling the observed line profiles and spectra with composite models (photoionization+shocks)…
Active galactic nuclei present continuum and line emission. The emission lines are originated by gas located close to the central super-massive black hole. Some of these lines are broad, and would be produced in a small region called…
Centaurus A (Cen A) is the closest radio galaxy and a prime example of a low-luminosity active galactic nucleus (AGN), exhibiting complex emissions across the electromagnetic spectrum. The nature of its continuum emission, particularly the…
We study the properties of the emission line regions in two samples of low luminosity radio-galaxies (LLRG), focusing on the compact emission line region (CELR) revealed to be a characteristic feature of these objects by HST narrow-band…
The narrow Fe K$\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei…
Low-ionization nuclear emission-line regions (LINERs), which exist in a large fraction of galaxies, may be the least luminous manifestation of quasar activity. The nature of LINERs has, however, remained controversial because an AGN-like…
The clear sign of a hidden quasar inside a radio galaxy is the appearance of quasar spectral features in its polarized (scattered) light. However that observational test requires suitably placed scattering material to act as a mirror,…
A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new…
We have studied the physical properties of a sample of narrow-line Seyfert 1 (NLS1) galaxies, and present a summary of our previous results, and new results. In particular, we have previously shown that (1) the locus of NLS1 galaxies on the…
The narrow emission line spectra of active galactic nuclei are not accurately described by simple photoionization models of single clouds. Recent Hubble Space Telescope images of Seyfert 2 galaxies show that these objects are rich with…
We analyze the high-resolution XRISM/Resolve spectrum of the Fe K$\alpha$ emission line of the nearest active galactic nucleus, in Centaurus A. The line features two narrow and resolved peaks of Fe K$\alpha_1$, and Fe K$\alpha_2$ with a…
We discuss here the spatial clustering of Seyferts and LINERs and consequences for their central engines. We show that Seyferts are less clustered than LINERs, and that this difference is not driven by the morphology-density relation, but…
It is not yet well known whether narrow line Seyfert 1 (NLS1) galaxies follow the $M_{BH} - \sigma_{\star}$ relation found for normal galaxies. Emission lines, such as [SII] or [OIII]$\lambda$5007, have been used as a surrogate of the…
We found a very large, 35 kpc, emission-line region around the Seyfert type 2 galaxy NGC 4388, using deep narrow-band imaging with the prime focus camera (Suprime-Cam) of the Subaru telescope. This region consists of many faint gas clouds…
We describe improved modelling of the emission by dust in a toroidal--like structure heated by a central illuminating source within Active Galactic Nuclei (AGN). We chose a simple but realistic torus geometry, a flared disc, and a dust…
We report results from multi-epoch X-ray observations of the polar-scattered Seyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectral variability from months to years timescales. The observed spectral variability is entirely…
We have newly identified a substantial number of type 1 active galactic nuclei (AGN) featuring weak broad-line regions (BLRs) at z < 0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects…
Active Galactic Nuclei (AGN) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight. However, except for a few special cases, the specific inclinations…
Coronal lines are a powerful, yet poorly understood, tool to identify and characterize Active Galactic Nuclei (AGNs). There have been few large scale surveys of coronal lines in the general galaxy population in the literature so far. Using…