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ALMA [CII] line and continuum observations of five redshift z>6 quasars are presented. This sample was selected to probe lower black hole mass quasars than most previous studies. We find a wide dispersion in properties with CFHQS J0216-0455, a low-luminosity quasar with absolute magnitude M_1450=-22.2, remaining undetected implying a limit on the star formation rate in the host galaxy of <10 solar masses per year, whereas other host galaxies have star formation rates up to hundreds of solar masses per year. Two other quasars have particularly interesting properties. VIMOS2911 is one of the least luminous z>6 quasars known with M_1450=-23.1, yet its host galaxy is experiencing a very powerful starburst. PSO J167-13 has a broad and luminous [CII] line and a neighbouring galaxy a projected distance of 5kpc away that is also detected in the [CII] line and continuum. Combining with similar observations from the literature, we study the ratio of [CII] line to far-infrared luminosity finding this ratio increases at high-redshift at a fixed far-infrared luminosity, likely due to lower dust content, lower metallicity and/or higher gas masses. We compile a sample of 21 high-redshift quasars with dynamical masses and investigate the relationship between black hole mass and dynamical mass. The new observations presented here reveal dynamical masses consistent with the relationship defined by local galaxies. However, the full sample shows a very wide scatter across the black hole mass - dynamical mass plane, whereas both the local relationship and simulations of high-redshift quasars show a much lower dispersion in dynamical mass.
We present ALMA observations of two moderate luminosity quasars at redshift 6. These quasars from the Canada-France High-z Quasar Survey (CFHQS) have black hole masses of ~10^8 M_solar. Both quasars are detected in the [CII] line and dust continuum.
Recent analysis of strongly-lensed sources in the Hubble Frontier Fields indicates that the rest-frame UV luminosity function of galaxies at $z=$6--8 rises as a power law down to $M_mathrm{UV}=-15$, and possibly as faint as -12.5. We use predictions
We present new H and K bands spectroscopy of 15 high luminosity active galactic nuclei (AGNs) at redshifts 2.3-3.4 obtained on Gemini South. We combined the data with spectra of additional 29 high-luminosity sources to obtain a sample with 10^{45.2}<
The local black hole mass function (BHMF) is of great interest to a variety of astrophysical problems, ranging from black hole binary merger rates to an indirect census of the dominant seeding mechanism of supermassive black holes. In this Letter, we
We present discovery observations of a quasar in the Canada-France High-z Quasar Survey (CFHQS) at redshift z=6.44. We also use near-IR spectroscopy of nine CFHQS quasars at z~6 to determine black hole masses. These are compared with similar estimate