Related papers: Profile variations in AGN spectra

We present near-infrared 1.5 - 2.5 micron moderate resolution long-slit spectra of two Seyfert 1 galaxies (NGC 1097 and NGC 1566), three Seyfert 2s (NGC 1386, NGC 4945 and NGC 5128) and one Seyfert 1.5 (NGC 3227), both parallel to…

We present new spectroscopic observations of an old case of anomalous redshift--NGC 7603 and its companion. The redshifts of the two galaxies which are apparently connected by a luminous filament are z=0.029 and z=0.057 respectively. We…

According to the unified model, the differences observed in different classes of AGN are due to anisotropic obscuration. This implies that in the hard X-rays, at energies where the radiation can pierce the obscuring material, the average…

Context. Our consortium performed an extensive multi-wavelength campaign of the nearby Seyfert 1 galaxy NGC 5548 in 2013-14. The source appeared unusually heavily absorbed in the soft X-rays, and signatures of outflowing absorption were…

We present the results of a long-term (1999--2010) spectral optical monitoring campaign of the active galactic nucleus (AGN) Ark 564, which shows a strong Fe II line emission in the optical. This AGN is a narrow line Seyfert 1 (NLS1)…

We model the broad emission lines present in the optical, UV and X-ray spectra of Mrk 509, a bright type 1 Seyfert galaxy. The broad lines were simultaneously observed during a large multiwavelength campaign, using the XMM-Newton-OM for the…

The broad (FWHM ~ 10,000 km/s) double-peaked H{\alpha} profile from the LINER/Seyfert 1 nucleus of NGC 1097 was discovered in 1991, and monitored for the following 11 years. The profile showed variations attributed to the rotation of gas in…

The results of spectropolarimetry surveys of obscured AGNs are reviewed, paying special attention to their implications for the existence of two populations of type 2 Seyfert galaxies -- hidden Seyfert 1s and "true" Seyfert 2s. In this…

We present results of an intensive two-month campaign of approximately daily spectrophotometric monitoring of the narrow-line Seyfert 1 galaxy Akn 564 with HST. The fractional variability amplitude of the continuum variations between…

To study the role of the feedback from the Active Galactic Nuclei (AGNs) in the evolution of its host galaxy, we need observational constraints on 100 pc scales. We used the Gemini Near Infrared Integral Field Spectrograph in the J and K…

We use X-ray monitoring data obtained over a broad range of time-scales to measure the broadband power spectral density functions (PSDs) of two Seyfert galaxies, the broad line Seyfert 1 NGC 3227 and the Seyfert 2 NGC 5506, which has…

Seyfert-type AGN that exhibit unusually strong and steep soft X-ray spectra are reviewed, building on observations made during the ROSAT all-sky survey. Two individual cases are described in brief detail, both being identified initially in…

We present the results regarding the analysis of an intensive monitoring of the Active Galactic Nucleus (AGN) NGC 7469. We observed the source for 4 months with almost daily cadence in the ugriz bands, using the IO:O on the Liverpool…

We report on the largest Swift AGN monitoring program, concerning UV/optical variability in Seyferts. From 554 observations, over a 750d period, of the Seyfert galaxy NGC 5548, we see (McHardy et al. 2014) a good overall correlation between…

We discuss the long-term evolution of the broad double-peaked H alpha profile of the LINER/Seyfert 1 nucleus of NGC 1097. Besides the previously known variation of the relative intensities of the blue and red peaks, the profile has recently…

Jetted Active Galactic Nuclei (AGN) exhibit variability across a wide range of time scales. Traditionally, this variability can often be modeled well as a stochastic process. However, in certain cases, jetted AGN variability displays…

We present preliminary results on the variability properties of AGN above 20 keV in order to show the potential of the INTEGRAL IBIS/ISGRI and Swift/BAT instruments for hard X-ray timing analysis of AGN. The 15-50 keV light curves of 36 AGN…

It has been shown that the luminosity of AGNs and the size of their broad line region obey a simple relation of the type R=a L^g, from faint Seyfert nuclei to bright quasars, allowing single-epoch determination of the central black hole…

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…

NGC~5548 is an X-ray bright Seyfert 1 active galaxy. It exhibits a variety of spectroscopic features in the soft X-ray band, including in particular the absorption by the AGN outflows of a broad range of ionization states, with column…