HE0450-2958, an interacting quasar-starburst galaxy pair at z = 0.285, is one of the best known examples of strong star formation activity in the presence of a quasardriven jet. We present new multi-band JVLA-imaging covering 1 to 6 GHz and reaching an angular resolution of up to 0. 6 (a 6-fold improvement over existing radio data). We confirm the previous detection of a spatially extended radi...

We present a quasar candidate identification technique based on multicolor photometry. The traditional multidimensional method (2 × N dimensions, where N is the number of the color-color diagrams) is reduced to a one-dimensional technique, which consists in a standard fitting procedure, where the observed spectral energy distributions are compared to quasar simulated spectra and stellar templat...

An empirically motivated model is presented for accretion-dominated growth of the super massive black holes (SMBH) in galaxies, and the implications are studied for the evolution of the quasar population in the universe. We investigate the core aspects of the quasar population, including space density evolution, evolution of the characteristic luminosity, plausible minimum masses of quasars, th...

As storage capacities increase, managing petabytes of data becomes increasingly challenging. One reason is the POSIX file system interface, originally designed in the 1970s in the context of file collections many orders of magnitude smaller than those found in today’s petabyte-scale storage systems. We show the scalability problems of the naming language imposed by POSIX, i.e. the language to i...

Using cosmological hydrodynamic simulations we measure the mean transmitted flux in the Lyα forest for quasar sightlines that pass near a foreground quasar. We find that the trend of absorption with pixel-quasar separation distance can be fitted using a simple power law form including the usual correlation function parameters r0 and γ so that (〈F (r)〉 = ∑ exp(−τeff(1 + ( r r0 )))). From the sim...

A brief overview is given of the current status of molecular emission line observations at high redshift. New observations are presented of CO in the gravitationally lensed quasar MG 0414+0534 (detected) and the unlensed quasar PG 1634+706 (not detected). Also noted are the results of a partially completed search for water maser emission in several redshift bands above z = 0.4.

We study the cross-correlation between quasars and galaxies by embedding models for the formation and evolution of the two populations in cosmological N-body simulations. We adopt the quasar evolution model of Kauffmann & Haehnelt (2000), in which supermassive black holes are formed and fuelled during major mergers. We define the “bias” parameter bQG as the ratio of the cross-correlation functi...

The Canada-France High-z Quasar Survey (CFHQS) is an optical survey designed to locate quasars during the epoch of reionization. In this paper we present the discovery of the first four CFHQS quasars at redshift greater than 6, including the most distant known quasar, CFHQS J2329-0301 at z = 6.43. We describe the observational method used to identify the quasars and present optical, infrared, a...

It is widely believed that the optical/UV continuum of quasars (the " Big Blue Bump ") represents optically thick thermal emission from accretion onto a black hole. Narrow line radio galaxies don't show such a component directly, and were historically thought for that reason to be rotation-powered, with large kinetic luminosity in the radio jets but very little accretion or optical radiation. W...

It is widely believed that the optical/UV continuum of quasars (the " Big Blue Bump ") represents optically thick thermal emission from accretion onto a black hole. Narrow line radio galaxies don't show such a component directly, and were historically thought for that reason to be rotation-powered, with large kinetic luminosity in the radio jets but very little accretion or optical radiation. W...