ESO key programme, gravitational lensing: quasars and radio galaxies; a status report

in Distribution of Matter in the Universe (1992, December 01)

The scientific background and objectives of our ESO Key Programme are first recalled. A brief account of our research activities (observing runs at ESO and elsewhere, meetings, etc.) is then given ... [more ▼]

The scientific background and objectives of our ESO Key Programme are first recalled. A brief account of our research activities (observing runs at ESO and elsewhere, meetings, etc.) is then given. Preliminary scientific results are presented concerning 1) our observational database for highly luminous quasars and distant powerful radiogalaxies; 2) speckle observations of highly luminous quasars; 3) the photometric monitoring and 4) detailed studies of several known gravitational lenses; 5) optical observations of 3C and 4C radio galaxies and 6) of the well known Einstein ring MG 1131+0456. [less ▲]

Discovery of a quadruply lensed quasar - The 'clover leaf' H1413 + 117

in Nature (1988), 334

The authors report the discovery of a second gravitational lens system in the broad absorption line quasar H1413+117. Four images of comparable brightness are seen, separated by â ¡1 arcsec. The unique ... [more ▼]

The authors report the discovery of a second gravitational lens system in the broad absorption line quasar H1413+117. Four images of comparable brightness are seen, separated by â ¡1 arcsec. The unique configuration of the images, together with the fairly rare occurrence of this type of quasar, makes it incontrovertible that this is a lensed system, not a cluster of quasars. (See also 159.062). [less ▲]

Search for Gravitational Lensing from a Survey of Highly Luminous Quasars

in Osmer, Patrick; Phillips, M. M. (Eds.) ASP Conference Series, Volume 2, Proceedings of a Workshop on Optical Surveys for Quasars (1988)

The authors have shown that their search for gravitational lensing from a survey of optically selected highly luminous quasars (HLQ) appears very promising. Observational features (multiple images, image ... [more ▼]

The authors have shown that their search for gravitational lensing from a survey of optically selected highly luminous quasars (HLQ) appears very promising. Observational features (multiple images, image elongation, jet-like feature, fuzz, etc.) possibly associated with the HLQ phenomenon have been detected for more than 20% of the objects under study. While it is not yet known how many of the HLQs are gravitational mirages, at least 5 (out of 111) of the investigated quasars appear to be highly luminous because of amplification of their brightness by gravitational lensing. [less ▲]

A new case of gravitational lensing

in Nature (1987), 329

The authors have begun a systematic search from ESO for gravitational lens systems in a selected sample of highly luminous quasars; M[SUB]V[/SUB] < -29.0. They give a brief description of their first ... [more ▼]

The authors have begun a systematic search from ESO for gravitational lens systems in a selected sample of highly luminous quasars; M[SUB]V[/SUB] < -29.0. They give a brief description of their first identified gravitational lens system UM673 = Q0142-100 = PHL3703. It consists of two images, A (m[SUB]R[/SUB] = 16.9) and B (m[SUB]R[/SUB] = 19.1), separated by 2.2 arc s at a redshift z[SUB]q[/SUB] = 2.719. The lensing galaxy (m[SUB]R[/SUB] â 19, Z[SUB]L[/SUB] â 0.49) has also been found. It lies very near the line connecting the two QSO images, â ¡0.8 arc s from the fainter one. A value M[SUB]0[/SUB] â 2.4×10[SUP]11[/SUP]M_sun; for the mass of the lensing galaxy and Deltat â 7 weeks for most likely travel-time difference between the two light paths to the QSO are found (assuming H[SUB]0[/SUB] = 75 km s[SUP]-1[/SUP]Mpc[SUP]-1[/SUP], q[SUB]0[/SUB] = 0). [less ▲]