Related papers: The Fundamental Plane of Quasars
The fundamental plane (FP) is a widely used tool to investigate the properties of early-type galaxies, and the tight relation between its parameters has spawned several cosmological applications, including its use as a distance indicator…
Although absorbed quasars are extremely important for our understanding of the energetics of the Universe, the main physical parameters of their central engines are still poorly known. In this work we present and study a complete sample of…
We have imaged a 45x45 sq. arcmin. area centered on the Hubble Deep Field (HDF) in UBVRI passbands, down to respective limiting magnitudes of approximately 21.5, 22.5, 22.2, 22.2, and 21.2. The principal goals of the survey are to identify…
QSOs allow study of the evolution of the relationship between black holes in galactic nuclei and their host galaxies. The black hole mass can be derived from the widths of the broad emission lines, and the stellar velocity dispersion…
We use high-resolution Hubble Space Telescope imaging data of dwarf galaxies in the Local Volume ($\lesssim 11$ Mpc) to parameterise 19 newly discovered nuclear star clusters (NSCs). Most of the clusters have stellar masses of…
We have obtained optical imaging with the Canada France Hawaii Telescope (CFHT) of 21 2MASS-selected QSOs of redshift greater than 0.3. This paper complements the sample of lower redshift 2MASS QSOs previously published. The QSOs have…
We determined C, N and alpha-element relative abundances in the gas surrounding six QSOs at an average redshift of < z > ~ 2.4, by studying six narrow associated absorption systems in UVES high-resolution spectra. We found five systems with…
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…
Studying a sample of both strongly and weakly active galactic nuclei with measured masses and 5 GHz and 2-10 keV core luminosities, together with a few galactic black holes simultaneously observed in the radio and X-ray bands, Merloni,…
We investigate the structural properties of nuclear star clusters in late-type spiral galaxies. More specifically, we fit analytical models to HST images of 39 nuclear clusters in order to determine their effective radii after correction…
We measure the correlation between black-hole mass $M_{\rm BH}$ and host stellar mass $M_*$ for a sample of 38 broad-line quasars at $0.2\lesssim z\lesssim 0.8$ (median redshift $z_{\rm med}=0.5$). The black-hole masses are derived from a…
We compare the host galaxies properties of BL Lac objects with those of radio loud quasars (RLQs) imaged by the WFPC2 on board of HST. The considered objects (z<0.5) are always well resolved and their host galaxies satisfactorily modelled…
We present host-galaxy velocity dispersions of 12 local (mainly Palomar-Green) quasi-stellar objects (QSOs) measured directly from the stellar CO absorption features in the H band. The mean bulge velocity dispersion of the QSOs in our…
In order to study the host galaxies of type 1 (broad-line) quasars, we present a semi-analytic modelling method to decompose the on-nucleus spectra of quasars into nuclear and host galaxy channels. The method uses the spatial information…
We present images of 29 post-starburst quasars (PSQs) from a Hubble Space Telescope (\emph{HST}) Advanced Camera for Surveys (ACS) Wide Field Channel Snapshot program. These broad-lined active galactic nuclei (AGN) possess the spectral…
We present results from a program of optical spectroscopy for 23 nearby galaxy emission-line nuclei. This investigation takes advantage of the spatial resolution of the Hubble Space Telescope to study the structure and energetics of the…
We present surface photometry for the central regions of a sample of 33 early-type (E, S0, and S0/a) galaxies observed at 1.6 microns (H band) using the Hubble Space Telescope (HST). We employ a new technique of two-dimensional fitting to…
We carry out a comparative analysis of the relation between the mass of supermassive black holes (BHs) and the stellar mass of their host galaxies at $0.2<z<1.7$ using well-matched observations and multiple state-of-the-art simulations…
Recent studies of black holes in the nuclei of both active and normal galaxies have yielded relationships that permit a physical interpretation of the principal components of the spectra of QSOs. It is shown that principal component (or…
Massive structures, such as galaxies, act as strong gravitational lenses on background sources. When the background source is a quasar, several lensed images are seen, as magnified or de-magnified versions of the same object. The detailed…