I present a brief review about our ideas concerning the origin and nature of the broad line emitting gas. This is one of the outstanding problems in quasar research. I suggest the establishment of a central data base of high quality quasar spectra as a means to realize an understanding of quasars.

Based on numerical simulations of gas-rich galaxy mergers, we discuss a model in which quasar activity is tied to the self-regulated growth of supermassive black holes in galaxies. The nuclear inflow of gas attending a galaxy collision triggers a starburst and feeds black hole growth, but for most of the duration of the starburst, the black hole is “buried”, being heavily obscured by surroundin...

The evolution of quasar clustering is investigated with a new sample of 388 quasars with 0.3 < z ≤ 2.2, B ≤ 20.5 and MB < −23, selected over an area of 24.6 deg 2 in the South Galactic Pole. Assuming a two-point correlation function of the form ξ(r) = (r/ro) , we detect clustering with r0 = 6.2 ± 1.6 h −1 comoving Mpc and ξ̄(r = 15 hMpc) = 3 r3 ∫ r 0 x ξ(x)dx = 0.52± 20 at an average redshift of...

Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that might exist in all quasars and could play a major role in feedback to galaxy evolution. The viability of BAL outflows as a feedback mechanism depends on their kinetic energies, as derived from the outflow velocities, column densities, and distances from the central quasar. We estimate these quantities for the q...

We report the discovery of a z = 2.83 quasar in the field of the cooling flow galaxy cluster Abell 478. This quasar was first detected in a submm survey of star forming galaxies at high redshifts, as the brightest source. We discuss the optical spectrum and far–IR spectral energy distribution (SED) of this object.

Der Beitrag stellt mit Quasar Enterprise einen durchgängigen, serviceorientierten Ansatz zur Gestaltung großer Anwendungslandschaften vor. Er verwendet ein Architektur-Framework zur Strukturierung der methodischen Schritte und führt ein Domänenmodell zur Präzisierung der Begrifflichkeiten und Entwicklungsartefakte ein. Die dargestellten methodischen Bausteine und Richtlinien beruhen auf langjäh...

We present Australia Telescope Compact Array radio continuum observations of the quasar/galaxy system HE0450−2958. An asymetric triple linear morphology is observed, with the central radio component coincident with the quasar core and a second radio component associated with a companion galaxy at a projected distance of 7 kpc from the quasar. The system obeys the far-infrared to radio continuum...

Observations indicate the mass above which ellipticals dominate the galaxy population increases with redshift over the range 0 < z < 2, implying that galaxies transition from the blue to red sequence in a manner consistent with “cosmic downsizing.” Theories predict that mergers between gas-rich blue galaxies produce ellipticals, with an associated phase of bright quasar activity which expels an...

We report the detection of strong CaII/MgII absorption lines at the quasar redshift in the narrow line quasar SDSS J2339−0912 (z = 0.6604). The quasar exhibits strong FeII, small Balmer emission line width and a very red B−K s color. Both the optical continuum and broad emission lines are reddened by SMC-like dust of E(B−V)≃1.0 mag, while its near-infrared color (J − K s = 1.60) shows little re...

We present a source and lens reconstruction for the optical Einstein ring gravitational lens system RXS J1131-1231. We resolve detail in the source, which is the host galaxy of a z = 0.658 quasar, down to a resolution of 0.045 arc seconds (this is the size of the smallest conclusively resolved structures, rather than the pixel scale), using a Bayesian technique with a realistic model for the pr...