Related papers: Quasar host galaxies in the SDSS Stripe 82
The discovery of luminous quasars at redshifts up to 7.5 demonstrates the existence of several billion M_sun supermassive black holes (SMBHs) less than a billion years after the Big Bang. They are accompanied by intense star formation in…
We investigate the evolutionary properties of a sample of quasars at 5<z<6.4 using the semi-analytical hierarchical model GAMETE/QSOdust. We find that the observed properties of these quasars are well reproduced by a common formation…
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 results on over 100 high-redshift quasars found in the Sloan Digital Sky Survey (SDSS), using automated selection algorithms applied to SDSS imaging data and with spectroscopic confirmation obtained during routine spectroscopic…
High-redshift quasars are important tracers of structure and evolution in the early universe. However, they are very rare and difficult to find when using color selection because of contamination from late-type dwarfs. High-redshift quasar…
We present K-band imaging and photometry of a sample of 52 radio loud quasars (RQs) selected from the B3 survey with flux densities above 0.5 Jy at 408 MHz. The optical completeness of the sample is 90% and the quasars cover the redshift…
We present preliminary results from HST imaging of radio-loud quasar hosts, covering a ~x100 range in radio luminosity but in a narrow redshift range (0.5 to 0.65). The sample was selected from our new, spectroscopically complete 7C survey…
We present the final results from our survey of luminous $z \sim $ 5.5 quasars. This is the first systematic quasar survey focusing on quasars at $z \sim$ 5.5, during the post-reionization epoch. It has been challenging to select quasars at…
We have undertaken deep optical imaging observations of three 6.2<z<6.5 quasar fields in the i' and z' filters. These data are used to search for foreground galaxies which are gravitationally lensing the quasars and distant galaxies…
We use a volume-limited sample of quasars in the Sloan Digital Sky Survey (SDSS) DR7 quasar catalog to identify quasar groups and address their statistical significance. This quasar sample has a uniform selection function on the sky and…
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…
Using cosmological hydrodynamic simulations we measure the mean transmitted flux in the Lyman alpha forest for quasar sightlines that pass near a foreground quasar. We find that the trend of absorption with pixel-quasar separation distance…
I review our knowledge of the properties of the host galaxies of radio-loud and radio-quiet quasars, both in comparison to each other and in the context of the general galaxy population. It is now clear that the hosts of radio-loud and…
The [CII] 158 $\mu$m emission line and the underlying far-infrared (FIR) dust continuum are important tracers for studying star formation and kinematic properties of early galaxies. We present a survey of the [CII] emission lines and FIR…
We present the results of fitting deep off-nuclear optical spectroscopy of radio-quiet quasars, radio-loud quasars and radio galaxies at z ~ 0.2 with evolutionary synthesis models of galaxy evolution. Our aim was to determine the age of the…
We investigated the star formation history and stellar populations of a sample of 205 Type I quasar host galaxies (0.1$<$z$<$0.35) and compared with normal (non-active) galaxies of the same mass and redshift within the volume of the Galaxy…
The bright emission from high-redshift quasars completely conceals their host galaxies in the rest-frame ultraviolet/optical, with detection of the hosts in these wavelengths eluding even the Hubble Space Telescope (HST) using detailed…
We report on a Hubble Space Telescope search for rest-frame ultraviolet emission from the host galaxies of five far-infrared-luminous $z\simeq{}6$ quasars and the $z=5.85$ hot-dust free quasar SDSS J0005-0006. We perform 2D surface…
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…
We present rest-frame UV and Ly-alpha images of spatially-resolved structures around five high-redshift radio-loud quasars obtained with the WFPC2 camera on the Hubble Space Telescope. We find that all five quasars are extended and this…