Related papers: A Large-Scale Search for Photometrically Variable …
Low Luminosity Active Galactic Nuclei (LLAGNs) are contaminated by the light of their host galaxies, thus they cannot be detected by the usual colour techniques. For this reason their evolution in cosmic time is poorly known. Variability is…
This is the first paper in a dedicated series to study the properties of the optically selected BLR-less AGNs (Active Galactic Nuclei with no-hidden central broad emission line regions). We carried out a systematic search for the BLR-less…
Optical variability is a key observational probe for studying the accretion dynamics and central engine physics of Active Galactic Nuclei (AGNs). The quality and completeness of light curves have a direct impact on variability studies,…
The extremes of Active Galactic Nuclei (AGN) variability offer valuable new insights into the drivers and physics of AGN. We discuss some of the most extreme cases of AGN variability; the highest amplitudes, deep minima states, extreme…
Massive black holes (BHs) in dwarf galaxies can provide strong constraints on BH seeds, however reliably detecting them is notoriously difficult. High resolution radio observations were recently used to identify accreting massive BHs in…
We develop a simple method to search for changing-look (CL) active galactic nucleus (AGN) candidates, and conduct a test run. In this method, optical variations of AGNs are monitored and CL-AGNs may appear to have a pattern of being bluer…
We are conducting an archival Swift program to measure multiwavelength variability in active galactic nuclei (AGN). This variability information will provide constraints on the geometry, physical conditions and processes of the structures…
Merger events can trigger gas accretion onto supermassive black holes (SMBHs) located at the centre of galaxies, and form close pairs of AGN. The fraction of AGN in pairs offers critical insights into the dynamics of galaxy interactions,…
We present two catalogues of active galactic nucleus (AGN) candidates selected from the latest data of two all-sky surveys -- Data Release 2 (DR2) of the \emph{Gaia} mission and the unWISE catalogue of the \emph{Wide-field Infrared Survey…
The co-evolution of host galaxies and the active black holes which reside in their centre is one of the most important topics in modern observational cosmology. Here we present a study of the properties of obscured Active Galactic Nuclei…
We use the multi-epoch, mid-infrared Spitzer Deep, Wide-Field Survey to investigate the variability of 474,179 objects in 8.1 deg^2 of the NDWFS Bootes field. We perform a Difference Image Analysis of the four available epochs between 2004…
In this paper, we investigate 2727 galaxies observed by MaNGA as of June 2016 to develop spatially resolved techniques for identifying signatures of active galactic nuclei (AGN). We identify 303 AGN candidates. The additional spatial…
We present a sample of hard X-ray selected candidate black holes (BHs) in 19 dwarf galaxies. BH candidates are identified by cross-matching a parent sample of ~44,000 local dwarf galaxies (M_stellar < 3 x 10^9 Msun, z<0.055) with the…
We explore the presence of active galactic nuclei (AGN)/black holes (BH) in Green Pea galaxies (GPs), motivated by the presence of high ionization emission lines such as HeII and [NeIII] in their optical spectra. In order to identify AGN…
We have conducted a systematic survey for z $<$ 0.04 active Galactic nuclei (AGNs) that may have changed spectral class over the past decade. We use SkyMapper, Pan-STARRS and the V\'eron-Cetty & V\'eron (2010) catalogue to search the entire…
The damped random walk (DRW) process is one of the most commonly used and simplest stochastic models to describe variability of active galactic nuclei (AGN). An AGN light curve can be converted to just two DRW model parameters - the signal…
Periodic variability in active galactic nuclei (AGN) light curves has been proposed as a signature of close supermassive black hole (SMBH) binaries. Recently, 181 candidate SMBH binaries were identified in Gaia DR3 based on apparently…
Active galactic nuclei (AGN) are variable on a wide range of timescales, though relatively few systematic variability surveys have been conducted. Previous broad-band (both spectral and temporal) variability surveys of AGN are limited in…
We present an analysis of the cluster X-ray morphology and active galactic nucleus (AGN) activity in nine $z\sim1$ galaxy clusters from the Massive and Distant Clusters of $WISE$ Survey (MaDCoWS) observed with $Chandra$. Using photon…
In this work we analyzed X-ray light curves of active galactic nucleus NGC 4051 obtained using Advanced CCD Imaging Spectrometer of Chandra satellite. Taking into account mainly flaring behaviour of AGNs we have used wavelet analysis for…