We report on an XMM-Newton observation of the most distant known quasar, SDSSp J104433.04–012502.2, at z = 5.80. We have detected this quasar with high significance in the rest-frame 3.4–13.6 keV band, making it the most distant cosmic object detected in X-rays; 32± 9 counts were collected. SDSSp J104433.04–012502.2 is notably X-ray weak relative to other luminous, optically selected quasars, w...

We present submillimetre photometry of 11 3CR and 6CE radio quasars of similar 151-MHz radio luminosity and redshifts to the radio galaxies studied at 1.3 < z < 2 by Archibald et al. (2001). We detect all bar one quasar at 850 μm, and five quasars are confirmed as dusty hyperluminous objects by detections at shorter wavelengths. Our observations reveal a clear difference between the submillimet...

The iron abundance relative to α-elements in the circumnuclear region of quasars is regarded as a clock of the star formation history and, more specifically, of the enrichment by type Ia supernovae (SNIa). We investigate the iron abundance in a sample of 22 quasars in the redshift range 3.0<z<6.4 by measuring their rest frame UV FeII bump, which is shifted into the near-IR, and by comparing it ...

Using a homogenous sample of 38,208 quasars with a sky coverage of ∼ 4000deg2 drawn from the SDSS Data Release Five quasar catalog, we study the dependence of quasar clustering on luminosity, virial black hole mass, quasar color, and radio loudness. At z < 2.5, quasar clustering depends weakly on luminosity and virial black hole mass, with typical uncertainty levels ∼ 10% for the measured corre...

We investigate the hypothesis that quasars formed together with the stellar populations of early-type galaxies. This hypothesis, in conjunction with the stellar ages of early-type galaxies from population synthesis models, the relation of black hole mass to bulge velocity dispersion, and the velocity dispersion distribution of spheroids from the Sloan Digital Sky Survey, completely determines t...

We have obtained complete redshift information for a sample of 442 radio-loud quasars with flux densities S 11 ≥ 0.25 Jy. These come from a completely-identified sample of 878 flat-spectrum radio sources, so there is no optical magnitude limit. With these quasars, therefore, we can map out the entire quasar epoch, unhindered by optical selection effects and any intervening dust. The rapid decli...

X-ray and optical observations of quadruply lensed quasars can provide a microarcsecond probe of the lensed quasar, corresponding to scale sizes of ∼ 102 − 104 gravitational radii of the central black hole. This high angular resolution is achieved by taking advantage of microlensing by stars in the lensing galaxy. In this paper we utilize X-ray observations of ten lensed quasars recorded with t...

In this letter, deep radio observations of the quasar PKS 0743−67 are presented that reveal a central engine capable of driving jets with enormous kinetic luminosity, Q > 4.1 × 10ergs/s. This result is significant because archival optical spectral data indicates that the accretion disk has a thermal luminosity, Lbol > 2×10 ergs/s. Furthermore, estimates of the central black hole mass from line ...

We show that the Lyman-α (Lyα) optical depth statistics in the proximity regions of quasar spectra depend sensitively on the mass of the dark matter halos hosting the quasars. This is owing to both the overdensity around the quasars and the associated infall of gas toward them. For a fiducial quasar host halo mass of 3.0± 1.6 h × 10 M⊙, as inferred by Croom et al. from clustering in the 2dF QSO...

We present a deep image of the optically-powerful quasar E 1821+643 at 18 cm made with the Very Large Array (VLA). This image reveals radio emission, over 280h kpc in extent, elongated way beyond the quasar’s host galaxy. Its radio structure has decreasing surface brightness with increasing distance from the bright core, characteristic of FR I sources (Fanaroff & Riley 1974). Its radio luminosi...