Related papers: Low redshift quasars in the SDSS Stripe 82. The ho…
We conduct a study of the gas kinematics of two quasar host galaxies at $z\gtrsim6$ traced by the [CII] emission line using ALMA. By combining deep observations at both low and high resolution, we recover the diffuse emission, resolve its…
We present the results of deep near-infrared observations of 11 hard X-ray selected sources in the Hellas2XMM survey, with faint optical magnitude (R>24) and high X-ray-to-optical flux ratio. All but one of the sources have been detected in…
We provide a simple theoretical model for the quasar luminosity function at high redshifts that naturally reproduces the statistical properties of the luminous SDSS quasar sample at redshifts z~4.3 and z>5.7. Our model is based on the…
Recent observations from the EIGER JWST program have measured for the first time the quasar-galaxy cross-correlation function at $z\approx6$. The auto-correlation function of faint $z\approx6$ quasars was also recently estimated. These…
We present the results of adaptive-optics imaging in the H and K bands of 12 low and intermediate redshift (z<0.6) quasars using the PUEO system mounted on the Canada-France-Hawaii telescope. Five quasars are radio-quiet and seven are…
We present a catalogue of 4098 photometrically selected galaxy clusters with a median redshift <z> = 0.32 in the 270 square degree 'Stripe 82' region of the Sloan Digital Sky Survey (SDSS), covering the celestial equator in the Southern…
We investigate the relationship between quasars and close companion galaxies using photometry and spectroscopy from the large data set of the SDSS DR16 survey. From the SDSS-QSO catalog of quasars, we selected objects with 0.1 < z < 0.35…
We characterise the distribution of quasars within dark matter halos using a direct measurement technique for the first time at redshifts as high as $z \sim 1$. Using the Planck Sunyaev-Zeldovich (SZ) catalogue for galaxy groups and the…
(abridged) We present near-infrared Ks-band imaging of 13 high redshift (0.6 < z < 1.3) BL Lac objects. We clearly detect the host in eight objects, and marginally in three others. In all cases, the host galaxy is well represented by an…
We test the hypothesis whether high redshift QSOs would preferentially appear in small groups or pairs, and if they are associated with massive, young clusters. We carried out a photometric search for \Ly emitters on scales $\lesssim 10…
In our first paper, we performed a detailed (i.e. bulge, disks, bars, spiral arms, rings, halo, nucleus, etc.) decomposition of 66 galaxies, with directly measured black hole masses, $M_{BH}$, that had been imaged at $3.6~\mu m$ with…
We have compiled a sample of 21 low redshift (z < 0.3), luminous active galactic nuclei (AGN) with large Balmer decrements (Halpha/Hbeta > 7) using the galaxy and QSO catalogs of the Sloan Digital Sky Survey Early Data Release. Using this…
Based on a recent photometric redshift galaxy catalogue, we have searched for galaxy clusters in the Stripe~82 region of the Sloan Digital Sky Survey by applying the Adami & MAzure Cluster FInder (AMACFI). Extensive tests were made to…
We explore the nature of heavily obscured quasar host galaxies at z~2 using deep Hubble Space Telescope WFC3/IR imaging of 28 Dust Obscured Galaxies (DOGs) to investigate the role of major mergers in driving black hole growth. The high…
For the first time spectroscopic galaxy redshift surveys are reaching the scales where galaxies can be studied together with the nearest quasars. This gives an opportunity to study the dependence between the activity of a quasar and its…
We present a compilation of HST images of 58 luminous SDSS type 2 AGNs at 0.3<z<0.4. 42 of them are type 2 quasars, which are a good representation of all optically selected SDSS type 2 quasars in this range. We find that the majority of…
We present Hubble Space Telescope 1.4-1.6 micron images of the hosts of ten extremely red quasars (ERQs) and six type 2 quasar candidates at z=2-3. ERQs, whose bolometric luminosities range between 10^47 and 10^48 erg/sec, show…
We present deep ground based imaging of the environments of five QSOs that contain sub-Damped Lyman-alpha systems at z<1 with the SOAR telescope and SOI camera. We detect a clear surplus of galaxies in these small fields, supporting the…
We used the Hubble Space Telescope WFC3 near-infrared camera to image the host galaxies of a sample of eleven luminous, dust-reddened quasars at z ~ 2 -- the peak epoch of black hole growth and star formation in the Universe -- to test the…
We present ALMA band 3 observations of the CO(6-5), CO(7-6), and [CI] 369micron emission lines in three of the highest redshift quasar host galaxies at 6.6<z<6.9. These measurements constitute the highest-redshift CO detections to date. The…