Related papers: Optical spectroscopy of type-2 LINERs
The hidden broad-line regions (BLRs) in Seyfert 2 galaxies, which display broad emission lines (BELs) in their polarized spectra, are a key piece of evidence in support of the unified model for active galactic nuclei (AGNs). However, the…
In this work we analyze a sample of AGN spectra, selected from the 6th Data Release of the Sloan Digital Sky Survey, exploiting a generalized technique of line profile analysis, designed to take into account the whole profiles of their…
We present a study of available Hubble Space Telescope (HST) spectroscopic and imaging observations of the low ionization nuclear emission line region (LINER) galaxy NGC 1052. The WFPC2 imagery clearly differentiates extended nebular Halpha…
A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from telescopes around the world, reveals that the Hbeta emission…
Outflows play a major role in the evolution of galaxies. However, we do not have yet a complete picture of their properties (extension, geometry, orientation and clumpiness). For low-luminosity Active Galactic Nuclei (AGNs), in particular,…
Double-peaked emission lines are observed in a small percentage of active galactic nuclei (AGN). These lines allow the determination of properties of the line-emitting region, known as the broad-line region (BLR). We investigated the…
We use ROSAT HRI spatial data and ASCA spectral measurements for a sample of seven nearby, early type spiral galaxies, to address the question of whether a low-luminosity Active Galactic Nucleus (LLAGN) is present in galaxies that have a…
Most massive galaxies show emission lines that can be characterized as LINERs. To what extent this emission is related to AGNs or to stellar processes is still an open question. In this paper, we analysed a sample of such galaxies to study…
We present results based on the analysis of optical spectra of KUG 1031+398, a Narrow Line Seyfert 1 (NLS1) galaxy for which Mason et al. (1996) reported evidence for a line-emitting region "intermediate" (both in terms of velocity and…
A 7.5 years spectrophotometric monitoring program of 28 Palomar-Green quasars to determine the size of their broad emission line region (BLR) is reviewed. We find both the continuum and the emission line fluxes of all quasars to vary during…
The broad-line region (BLR) of active galactic nuclei (AGNs) traces gas close to the central supermassive black hole (BH). Recent reverberation mapping (RM) and interferometric spectro-astrometry data have enabled detailed investigations of…
Using a well known method for laboratory plasma diagnostic, the Boltzmann-plot, we discuss the physical properties in Broad Line Region (BLR) of Active Galactic Nuclei (AGN). We apply the Boltzmann-plot method to Balmer lines on a sample of…
In this work, we investigated the nitrogen and oxygen abundances in a sample of galaxies with Low Ionization Nuclear Emission Regions (LINERs) in their nucleus. Optical spectroscopic data (3 600 - 10 000 {\AA}) of 40 LINERs from the Mapping…
The origin of outflow in narrow-line region (NLR) of active galactic nucleus (AGN) is studied in this paper by focusing on the relationship between the [\ion{O}{3}]$\lambda$5007 line profile and the hard X-ray (in a bandpass of 2-10 keV)…
We report the discovery of an extremely broad H-alpha emission line in the LINER nucleus of NGC 4579. From ground-based observations, the galaxy was previously known to contain a Type 1 nucleus with a broad H-alpha line of FWHM = 2300 km/s…
"Changing-look active galactic nuclei" (CLAGNs) are known to change their apparent types between types 1 and 2, usually accompanied by a drastic change in their luminosity on timescales of years. However, it is still unclear whether…
We have conducted a comprehensive mid-IR spectroscopic investigation of 67 Low Ionization Nuclear Emission Line Regions (LINERs) using archival observations from the high resolution modules of the Infrared Spectrograph on board the Spitzer…
We analyze the ratios of the broad hydrogen Balmer emission lines (from H\alpha to H\epsilon) in the context of estimating the physical conditions in the broad line region (BLR) of active galactic nuclei (AGN). The Balmer emission lines are…
Most of the optically classified low ionisation narrow emission-line regions (LINERs) nuclei host an active galactic nuclei (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. The aims of this work are…
We present the study of the gas kinematics in narrow-line regions (NLRs) of 2,009 type-2 AGNs at $z<0.34$. We construct the [O III]$\lambda$5007 emission-line images using publicly available broadband images from the Sloan Digital Sky…