Related papers: The Apparently Normal Galaxy Hosts for Two Luminou…
We have performed HST imaging of a sample of 23 high-redshift (1.8<z<2.75) AGN, drawn from the COMBO-17 survey. The sample contains moderately luminous quasars (M_B ~ -23). The data are part of the GEMS imaging survey that provides high…
We present near-infrared H-band observations of the hosts of three z~1 quasars from the Sloan Digital Sky Survey made with the adaptive optics system at Lick Observatory. We derive a PSF for each quasar and model the host plus quasar…
We have undertaken a project to investigate the host galaxies and environments of a sample of quasars at z~4. In this paper, we describe deep near-infrared imaging of 34 targets using the Magellan I and Gemini North telescopes. We discuss…
Cool ($T\sim10^4$~K) gas is commonly observed around $z>2$ quasars as traced by extended Ly$\alpha$ emission. These large-scale nebulae are usually studied using circularly averaged surface brightness profiles, which suppress information on…
We report the discovery of a new bright quasar PHL 1811 as part of a followup program to identify bright quasars in the FIRST radio survey. With B=13.9, R=13.9, and z=0.192, this quasar is now the second brightest quasar (in apparent…
The properties of high redshift quasar host galaxies are studied, in order to investigate the connection between galaxy evolution, nuclear activity, and the formation of supermassive black holes. We combine new near-infrared observations of…
We present multicolour Hubble Space Telescope images of the powerful z=2.4 radio galaxy MRC 0406-244 and model its complex morphology with several components including a host galaxy, a point source, and extended nebular and continuum…
We investigate multicolour imaging data of a complete sample of 19 low redshift (z<0.2) quasar host galaxies. The sample was imaged in four optical (BVRi) and three near-infrared bands (JHK_s). Galaxy types, structural parameters and robust…
We present spectra taken with the Low Resolution Imaging Spectrograph on the Keck 10m telescope of spatially-resolved structures ("fuzz") around the high-redshift radio-loud quasars PKS 0445+097 (z=2.108) and PKS 2338+042 (z=2.589). For PKS…
Magain et al. (2005) argued that the host galaxy of the quasar in HE0450-2958 is substantially under-luminous given the likely mass of its nuclear black hole. Using kinematical information from the spectra of the quasar and the companion…
We study quasar proximity zones in a simulation that includes a self-consistent quasar formation model and realistic IGM environments. The quasar host halo is $10^{13}\ M_{\mathrm{\odot}}$ at $z=6$, more massive than typical halos studied…
We present deep Gemini GMOS optical spectroscopy of nine luminous quasars at redshifts z ~ 0.5, drawn from the SDSS type 2 quasar sample. Our targets were selected to have high intrinsic luminosities (M_V < -26 mag) as indicated by the [O…
The stellar properties of about 800 galaxies hosting optically luminous, unobscured quasars at z < 0.6 are analyzed. Deep co-added Sloan Digital Sky Survey (SDSS) images of the quasars on Stripe 82 are decomposed into nucleus and host…
Hubble Space Telescope observations of the gravitational lens PG 1115+080 in the infrared show the known z =0.310 lens galaxy and reveal the z = 1.722 quasar host galaxy. The main lens galaxy G is a nearly circular (ellipticity < 0.07)…
We examine the clustering of galaxies around a sample of 20 luminous low redshift (z<0.30) quasars observed with the Wide Field Camera-2 on the Hubble Space Telescope. The HST resolution makes possible galaxy identification brighter than…
We construct a sample of 3,516 radio-loud host galaxies of active galactic nuclei (AGN) from the optical Sloan Digital Sky Survey (SDSS) and Faint Images of the Radio Sky at Twenty cm (FIRST). These have 1.4 GHz luminosities in the range…
We present the results from a survey of i-dropout objects selected from ~1550 deg^2 of multicolor imaging data from the Sloan Digital Sky Survey, to search for luminous quasars at z>5.8. Objects with i*-z*>2.2 and z*<20.2 are selected, and…
We present medium resolution near-infrared host galaxy spectra of low redshift quasars, PG 0844 + 349 (z=0.064), PG 1226 + 023 (z=0.158), and PG 1426+015 (z=0.086). The observations were done by using the Infrared Camera and Spectrograph…
We report the results from a deep HST NICMOS H-band imaging survey of a carefully selected sample of 33 luminous, late-stage galactic mergers at z < 0.3. Signs of a recent galactic interaction are seen in all of the objects in the HST…
We expect luminous ($M_{1450}\lesssim-26.5$) high-redshift quasars to trace the highest density peaks in the early universe. Here, we present observations of four $z\gtrsim6$ quasar fields using JWST/NIRCam in imaging and widefield slitless…