Related papers: Extended Coronal Emission Lines in Active Galactic…

Narrow Line Seyfert 1 galaxies represent a distinct category in the larger family of Type 1 Active Galactic Nuclei. The occurrence of emission line profiles not broader than 2000 km/s, combined with luminosity estimates comparable to those…

A thorough study of radio emission in Active Galactic Nuclei (AGN) is of fundamental importance to understand the physical mechanisms responsible for the emission and the interplay between accretion and ejection processes. High frequency…

We report preliminary results from an arcsecond-resolution X-ray survey of nearby galaxies using ACIS on board Chandra. The total sample consists of 41 low-luminosity AGNs, including Seyferts, LINERs, and LINER/H II transition objects. In…

We present a catalog of Local Universe Near-Infrared Seyfert (LUNIS) \textit{K-}band integral field unit (IFU) data of 88 nearby Active Galactic Nuclei (AGN), curated from SINFONI/VLT and OSIRIS/Keck archival datasets. This catalog includes…

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…

(abridged) I present and discuss the results of HST STIS observations of IRAS 13224-3809 and 1H 0707-495, two narrow-line Seyfert 1 (NLS1) galaxies. We discovered that high-ionization UV emission lines are much broader and strongly…

We present J-band long-slit spectroscopic observation of NGC 1068 classified as a Seyfert 2 galaxy. J-band observations with OAO/ISLE provide clear detection of spatially extended [Fe II]1.257um and [P II]1.188um lines. We found that [Fe…

We present new HST ACS medium- and narrow-band images and long-slit, optical (4000 - 7200A) spectra obtained using the Isaac Newton Telescope (INT) on La Palma, of the merging system Mrk273. The HST observations sample the [OIII]4959,5007…

Ionization cones and relativistic jets give us one of the most large-scale example of active galactic nuclei (AGN) influence on the surrounding gas environment in galaxies and beyond. The study of ionization cones makes it possible not only…

The narrow line region of active galaxies is formed by gas clouds surrounded by a diluted gas. Standard one-dimensional photoionization models are usually used to model this region in order to reproduce the observed emission lines. Since…

Anisotropic emission of the ionizing continuum is a general prediction of the accretion disk models. In this paper, we present the results of correlation analysis of the UV emission line and UV to X-ray continuum properties for a large…

We have examined the physical conditions within a bright emission-line knot in the inner narrow-line region (NLR) of the Seyfert 2 galaxy Mrk 573 using optical spectra and photoionization models. The spectra were obtained with the Hubble…

Ultraviolet spectroscopy of the extended solar corona is a powerful tool for measuring the properties of protons, electrons, and heavy ions in the accelerating solar wind. The large coronal holes that expand up from the north and south…

In this contribution we report on the study of the optical emission lines and X-ray spectra of a sample of Type 1 AGNs, collected at the Sloan Digital Sky Survey database and observed by the XMM Newton satellite. Exploiting the different…

We have compared the optical emission line ratios of type 2 quasars from Zakamska et al. with standard AGN photoionization model predictions, Seyfert 2s, HII galaxies, and narrow line FRII radio galaxies. Moderate to high ionization narrow…

Since the discovery of active galactic nuclei (AGN) and their subclasses, a unification scheme of AGN has been long sought. Orientation-based unified models predict that some of the diversity within AGN subclasses can be explained by the…

New observations using narrow band imaging, long-slit spectroscopy and MERLIN observations of the nuclear region of the Seyfert galaxy NGC~4051 have been made. An edge brightened, triangular region of ionized gas extending 420 pc from the…

This is the second in a series of papers aiming to test how the mass ($M_{\rm BH}$), accretion rate ($\dot{M}$) and spin ($a_{*}$) of super massive black holes (SMBHs) determine the observed properties of type-I active galactic nuclei…

We present theoretical iron emission line strengths for physical conditions typical of Active Galactic Nuclei with Broad-Line Regions. The non-local thermodynamic equilibrium (NLTE) models include a new and extensive treatment of radiative…

We present a detailed analysis of oxygen ion velocity distributions in the extended solar corona, based on observations made with the Ultraviolet Coronagraph Spectrometer (UVCS) on the SOHO spacecraft. Polar coronal holes at solar minimum…