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An optical imaging survey for gravitational lenses and the discovery of a new lens candidate

Djorgovski, S. and Meylan, G. (1989) An optical imaging survey for gravitational lenses and the discovery of a new lens candidate. In: Gravitational Lenses. Lecture Notes in Physics. No.330. Springer , Berlin, pp. 173-178. ISBN 978-3-540-51061-1.

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We are conducting an optical imaging search for gravitational lenses. A sample of known quasars was selected on the basis of high redshifts and apparently large absolute luminosities; these selection criteria significantly enhance the probability that a given QSO is gravitationally magnified. So far, our search has yielded at least one new gravitational lens system, associated with the quasar UM 425 = 1120+019,,one binary quasar, PKS 1145-071, and several other promising candidates that still need spectroscopic confirmation. In addition, we found several cases of foreground galaxies within a few arcsec from the quasars, which should be useful for absorption line studies. The optical image of the UM 425 system consists of four or more components, at least two of which have identical spectra. There are many faint galaxies in the field, suggestive of a lensing cluster at a redshift of several tenths, and tentative evidence for a z ≅ 0.6 galaxy underlying the second-brightest quasar image. We conclude that the heuristically designed optical searches for gravitational lenses can successfully complement the radio-based surveys.

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Djorgovski, S.0000-0002-0603-3087
Additional Information:© 1989 Springer-Verlag. We are greatly indebted to the staffs of CTIO, ESO, KPNO, MMTO, Palomar, and Las Campanas observatories for their valuable and professional help during the many observing runs. Rick Perley, Peter Shaver, and others, collaborated with us on several projects related to our survey. Finally, we acknowledge partial financial support from California Institute of Technology (S.D.) and European Southern Observatory (G.M.).
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European Southern Observatory (ESO)UNSPECIFIED
Series Name:Lecture Notes in Physics
Issue or Number:330
Record Number:CaltechAUTHORS:20190605-104442161
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:96143
Deposited By: Tony Diaz
Deposited On:06 Jun 2019 04:43
Last Modified:16 Nov 2021 17:18

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