Related papers: LINERs and their Physical Mechanisms
We study a complete and distance-limited sample of 25 LINERs, 21 of which have been imaged with the Hubble Space Telescope to study their physical properties and to compare their radio and optical properties with those of other samples of…
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 present an analysis of the optical line emission from nearby barred galaxies, and in particular look at the radial range occupied by the bar. In many cases this region is marked by what we term a 'star formation desert', with a marked…
Active galactic nuclei (AGN) are characterized by similar broad emission lines properties at all luminosities ($10^{39}$-$10^{47}$ erg s$^{-1}$). What produces this similarity over a vast range of $10^8$ in luminosity? Photoionization is…
X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs)…
The nucleus of M87 displays a LINER spectrum at optical wavelengths, with a nuclear disk of nebulosity that is resolved by the Hubble Space Telescope. We present new results from optical and ultraviolet spectra of the central ~40pc as…
This work studies the optical emission line properties and physical conditions of the narrow line region (NLR) of seven narrow-line Seyfert 1 galaxies (NLS1). Our results show that the flux carried out by the narrow component of H-beta is,…
We present the highlights from our recent study of 22 local (z$<$0.025) type-1 LINERs from the Palomar Survey, on the basis of optical long-slit spectroscopic observations taken with TWIN/CAHA, ALFOSC/NOT and HST/STIS (Cazzoli et al. 2018).…
Although the properties of the narrow-line region (NLR) of active galactic nuclei(AGN) have been deeply studied by many authors in the past three decades, many questions are still open. The main goal of this work is to explore the NLR of…
We report results from the first mid-infrared spectroscopic study of a comprehensive sample of 33 LINERs, observed with the Spitzer Space Telescope. We compare the properties of two different LINER populations: infrared-faint LINERs, with…
The high-ionization mid-IR lines, excited in the Narrow Line Regions (NLR) of Active Galactic Nuclei (AGN), barely affected by stellar excitation and dust extinction, trace the AGN bolometric power. We used the complete 12 micron sample of…
Based on a new spectroscopic sample observed using the WHT, we examine the kinematic properties of the various emission line regions in narrow line Seyfert 1 galaxies (NLS1s) by modelling their profiles using multiple component fits. We…
This paper reports the results of a near infrared spectroscopic survey of LINER galaxies undertaken with a new infrared spectrograph at the 5 m Hale telescope. The galaxy sample includes 11 LINERs with spectra covering the [FeII] (1.2567…
A sample of 229618 narrow emission-line galaxies is used to establish two new unambiguous type of evidence for supermassive black holes at the center of their nuclei: 1) the Seyfert 2 galaxies and LINERs follow the same characteristic power…
We investigate the physical cause of the great range in the ionization level seen in the spectra of narrow lined active galactic nuclei (AGN). Mean field independent component analysis identifies examples of individual SDSS galaxies whose…
We present high quality (high signal-to-noise ratio and moderate spectral resolution) near-infrared (near-IR) spectroscopic observations of 23 well-known broad-emission line active galactic nuclei (AGN). Additionally, we obtained…
Early studies of nearby Seyfert galaxies have led to the picture that the Narrow Line Region (NLR) is a cone-shaped region of gas ionized by radiation from a nuclear source collimated by a dusty torus, where the gas is in outflow. In this…
In order to determine whether unified models of active galactic nuclei apply to low-luminosity objects, we have undertaken a spectropolarimetric survey of of LINERs and Seyfert nuclei at the Keck Observatory. The 14 objects observed have a…
Using the SEDs of the weak AGNs 35 LINERs presented in a companion paper, we assess whether photoionization by the weak AGN can power the emission-line luminosities measured through the large (few-arcsecond) apertures used in ground-based…
We present X-ray observations of nine Weak-Line Radio Galaxies (WLRGs), optically classified as confirmed or possible Low Ionization Nuclear Emission-line Regions (LINERs). The data were taken from the Chandra, XMM, and BeppoSax archives.…