Related papers: The Smallest AGN Host Galaxies
We present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements…
Dwarf galaxies are ideal laboratories to probe the interplay between galaxy formation and the growth of black holes (BHs) in the early Universe. Mounting observational evidence reveals the presence of BHs in low-mass galaxies across cosmic…
Supermassive black holes (SMBHs) have been found to be ubiquitous in the nuclei of early-type galaxies and of bulges of spirals. There are evidences of a tight correlation between the SMBH masses, the velocity dispersions of stars in the…
We present a study of the host bulge properties and their relations with the black hole mass on a sample of 10 intermediate-type active galactic nuclei (AGN). Our sample consists mainly of early type spirals, four of them hosting a bar. For…
The recent observations of highly accreting supermassive black holes (SMBH) at very high redshift ($>$4) with the James Webb Space Telescope (JWST) allowed us to shed light for the very first time on the early evolutionary phases of active…
We measured the stellar velocity dispersions of 15 active galactic nucleus (AGN) host galaxies at redshifts as high as $\sim 0.34$. Combining these with published velocity dispersion measurements from the literature, we study the…
The tight correlations between the mass of supermassive black holes ($M_{\rm BH}$) and their host-galaxy properties have been of great interest to the astrophysical community, but a clear understanding of their origin and fundamental…
JWST observations have unveiled faint active galactic nuclei (AGN) at high-redshift that provide insights on the formation of supermassive black holes (SMBHs) and their coevolution with galaxies. However, disentangling stellar from AGN…
Effectively finding and identifying active galactic nuclei (AGNs) in dwarf galaxies is an important step in studying black hole formation and evolution. In this work, we examine four mid-IR-selected AGN candidates in dwarf galaxies with…
I provide a short review of the properties of Narrow-line Seyfert 1 (NLS1) galaxies across the electromagnetic spectrum and of the models to explain them. Their continuum and emission-line properties manifest one extreme form of Seyfert…
In the last decade, there have been several discoveries of Active Galactic Nuclei (AGN) in dwarf galaxies including an AGN in an ultra-compact dwarf galaxy with a Black Hole mass $>$10$^{6}$ M$_{\odot}$. However, finding a Supermassive…
We investigate the relationship between the present day optical luminosity function of galaxies and the X-ray luminosity function of Seyfert 1s to determine the fraction of galaxies which host Seyfert 1 nuclei and their Eddington ratios.…
In the local Universe, supermassive black hole (SMBH) masses strongly correlate with their host-galaxies' stellar masses ($M_{*}$), but galaxies hosting faint AGN recently found by JWST may deviate from this relation. To constrain the…
The ability to accurately discern active massive black holes (BHs) in nearby dwarf galaxies is paramount to understanding the origins and processes of "seed" BHs in the early Universe. We present Chandra X-ray Observatory observations of a…
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 have measured the stellar velocity dispersions (\sigma_*) and estimated the central black hole (BH) masses for over 900 broad-line active galactic nuclei (AGNs) observed with the Sloan Digital Sky Survey. The sample includes objects…
Mathur (2000) has proposed that the narrow line Seyfert 1 galaxies (NLS1s) are likely to be the active galaxies in early stage of evolution. To test this hypothesis, we have calculated the black hole (BH) masses and the host galaxy bulge…
In this work we aim at addressing the still open question about the nature of Narrow-Line Seyfert 1 (NLS1) galaxies: are they really active nuclei with lower mass Black-Holes (BHs) than Seyfert 1 (S1) and quasars? Our approach is based on…
We present the emission properties of a sample of 3,579 type 1 AGN, selected based on the detection of broad H-alpha emission. The sample covers the range of black hole mass 10^6<M_BH/M_Sun<10^9.5 and luminosity in Eddington units 10^-3 <…
A new sample of 204 low-mass black holes (LMBHs) in active galactic nuclei (AGNs) is presented with black hole masses in the range of (1-20) * 10^5 M_sun. The AGNs are selected from a systematic search among galaxies in the Seventh Data…