Related papers: The extended narrow-line region of two type-I quas…
Spatially resolved emission-line spectroscopy is a powerful tool to determine the physical conditions in the narrow-line region (NLR) of active galactic nuclei (AGNs). We recently used optical long-slit spectroscopy to study the NLRs of a…
We have observed the narrow-line regions (NLRs) of the seven brightest radio-quiet PG (or BQS) quasars (z < 0.5) with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST). Linear-ramp filters were used to image…
We study the narrow-line region (NLR) of six Seyfert-1 and six Seyfert-2 galaxies by means of spatially resolved optical spectroscopy and photoionization modelling. From spatially resolved spectral diagnostics, we find a transition between…
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…
While [OIII] narrow-band imaging is commonly used to measure the size of the narrow-line regions (NLRs) in active galactic nuclei (AGNs), it can be contaminated by emission from surrounding starbursts. Recently, we have shown that long-slit…
(Abridged) We present a detailed analysis of a large sample of 31 low-redshift, mostly radio-quiet type 1 QSOs observed with integral field spectroscopy to study their extended emission-line regions (EELRs). We focus on the ionisation state…
We have investigated the physical conditions in the narrow-line region (NLR) of M51 using long-slit spectra obtained with the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST) and 3.6 cm radio continuum…
We propose two statistical tests to investigate how we see the nuclear region (r < 0.1 pc) of Narrow-Line Seyfert 1 galaxies (NLS1s). 1) The high-ionization nuclear emission-line region (HINER) test: Seyfert 1 galaxies (S1s) have…
The [O III] $\lambda\lambda$ 4959,5007 lines are a useful proxy to test the kinematic of the narrow-line region (NLR) in active galactic nuclei (AGN). In AGN, and particularly in narrow-line Seyfert 1 galaxies (NLS1s) these lines often show…
It is known that the spectral energy distribution (SED) of the nuclear radiation of narrow-line Seyfert 1 galaxies (NLS1s) has different shapes with respect to that of ordinary broad-line Seyfert 1 galaxies (BLS1s), particularly in…
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)…
We compare the excitation of the Narrow-Line Region (NLR) of type 1 and type 2 QSOs for redshifts $0.4 \le z \le 0.5$ via the analysis of their emission line properties in Sloan Digital Sky Survey (SDSS) near-UV/optical spectra. We fit the…
We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies. We present and analyse high-sensitivity VLA radio continuum images of…
We report near-infrared spectroscopic data for the Seyfert 2 galaxy Mrk 78, taken with the LIRIS near-infrared camera/spectrometer at the William Herschel Telescope (WHT). The long-slit spectra clearly show extended emission. The resolution…
Interactions between the radio jet and the optical emission of the narrow-line region (NLR) are a well known phenomenon in Seyfert galaxies. Here, we present the study of possible jet-NLR interactions in five radio-quiet PG quasars with…
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…
Narrow-line Seyfert 1 galaxies (NLS1) are an intriguing subclass of active galactic nuclei. Their observed properties indicate low central black hole mass and high accretion rate. The extremely radio-loud NLS1 sources often show…
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 evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow (emission) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. 1) Hubble Space…
We present a study of high-resolution long-slit spectra of the narrow-line region (NLR) in NGC 1068 obtained with the Space Telescope Imaging Spectrograph (STIS) aboard The Hubble Space Telescope (HST). The spectra were retrieved from the…