Related papers: AGN Activity in Nucleated Galaxies as Measured by …
We present results of recurrence analysis of 46 active galactic nuclei (AGN) using light curves from the 157-month catalog of the Swift Burst Alert Telescope (BAT) in the 14-150 keV band. We generate recurrence plots and compute recurrence…
We present the X-ray spectral analysis of the 1855 extragalactic sources in the Chandra COSMOS-Legacy survey catalog having more than 30 net counts in the 0.5-7 keV band. 38% of the sources are optically classified Type 1 active galactic…
We present the results from an X-ray spectral analysis of active galactic nuclei (AGN) in the Chandra Deep Field-South, AEGIS-XD and Chandra-COSMOS surveys, focussing on the identification and characterisation of the most heavily obscured,…
Identifying Active Galactic Nuclei (AGNs) through their X-ray emission is efficient, but necessarily biased against X-ray-faint objects. We aim to characterize this bias by comparing X-ray-selected AGNs to the ones identified through…
The relation between nuclear ($\lesssim$ 50 pc) star formation and nuclear galactic activity is still elusive: theoretical models predict a link between the two, but it is unclear whether active galactic nuclei (AGNs) should appear at the…
We have conducted a high-resolution spectroscopic study using Spitzer of 18 bulgeless (Sd/Sdm) galaxies that show no definitive signatures of nuclear activity in their optical spectra. This is the first systematic mid-IR search for weak or…
We present NIR spectroscopy using MMT/MMIRS for a sample of twenty-nine massive galaxies ($\mathrm{log\ M_* / M_{\odot} \gtrsim10}$) at $\mathrm{z\sim0.7}$ with optical spectroscopy from the LEGA-C survey. Having both optical and NIR…
The 500ks Chandra ACIS-I observation of the field around the $z=6.31$ quasar SDSS J1030+0524 is currently the 5th deepest extragalactic X-ray survey. The rich multi-band coverage of the field allowed for an effective identification and…
This study explores the space density and properties of active galaxies to z=0.8. We have investigated the frequency and nature of unresolved nuclei in galaxies at moderate redshift as indicators of nuclear activity such as Active Galactic…
We present a comprehensive analysis of the X-ray spectral properties of 198 newly identified active galactic nuclei (AGNs), leveraging archival data from the {\it Chandra} X-ray Observatory. All these AGNs exhibit a powerlaw spectral…
We present near-infrared (NIR) spectroscopic observations of 28 X-ray and mid-infrared selected sources at a median redshift of z~0.8 in the Extended Groth Strip (EGS). To date this is the largest compilation of NIR spectra of active…
In order to understand the interactions between active galactic nuclei (AGN) and star formation during the evolution of galaxies, we investigate 142 galaxies detected in both X-ray and 70{\mu}m observations in the COSMOS (Cosmic Evolution…
Reliably identifying active galactic nuclei (AGNs) in dwarf galaxies is key to understanding black hole demographics at low masses and constraining models for black hole seed formation. Here we present Chandra X-ray Observatory observations…
We present a study of the prevalence and luminosity of Active Galactic Nuclei (AGN; traced by optical spectra) as a function of both environment and galaxy interactions. For this study we used a sample of more than 250000 galaxies drawn…
The impact of Active Galactic Nuclei (AGN) on star formation has implications for our understanding of the relationships between supermassive black holes and their galaxies, as well as for the growth of galaxies over the history of the…
We investigate the multi-wavelength properties of host galaxies of 3701 X-ray-selected active galactic nuclei (AGNs) out to z~5 in the Chandra-COSMOS Legacy Survey. Thanks to the extensive multi-wavelength photometry available in the COSMOS…
We analysed 385 galactic spectra from the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) that belong to the catalog of isolated pairs of galaxies by Karachentsev. The spectra corresponds to physical pairs of galaxies as defined by V…
Motivated by the apparently conflicting results reported in the literature on the effect of environment on nuclear activity, we have carried out a new analysis by comparing the fraction of galaxies hosting active galactic nuclei (AGNs) in…
To better understand the mechanism or mechanisms that lead to AGN activity today, we measure the X-ray AGN fraction in a new sample of nearby clusters and examine how it varies with galaxy properties, projected cluster-centric radius, and…
We investigate the role of galaxy mergers in triggering AGN in the nearby Universe. Our analysis is based on a sample of 79 post-merger remnant galaxies with deep X-ray observations from Chandra/XMM-Newton capable of detecting a…