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1608+656: A Quadruple Lens System Found in the Class Gravitational Lens Survey

Myers, Steven T. and Fassnacht, C. D. and Pearson, T. J. and Readhead, A. C. S. and Shepherd, M. C. and Blandford, R. D. and Browne, I. W. A. and Jackson, N. and Muxlow, T. and Nair, S. and Sykes, C. and Wilkinson, P. N. and de Bruyn, A. G. and Bremer, M. and Miley, G. K. and Schilizzi, R. T. and Snellen, I. A. G. and Djorgovski, S. G. and Matthews, K. and Neugebauer, G. and Smith, J. D. and Thompson, D. J. and Womble, D. S. (1996) 1608+656: A Quadruple Lens System Found in the Class Gravitational Lens Survey. In: Astrophysical Applications of Gravitational Lensing. International Astronomical Union Symposium (IAUS). No.173. Springer , Dordrecht, pp. 317-322. ISBN 978-0-7923-3955-7.

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The first phase of a large gravitational lens survey using the Very Large Array at a wavelength of 3.6 cm has been completed, yielding images for 3258 radio sources. The Cosmic Lens All-Sky Survey, or CLASS, is designed to locate gravitational lens systems consisting of multiply-imaged compact components with separations > 0″.2. From this first phase has come the discovery of 1608+656, a quadruply-imaged object with maximum separation of 2″.1. Images from the Palomar 5-m and Keck 10-m telescopes show the lensed images and the lensing galaxy. An optical spectrum obtained with the Palomar 5-m Telescope indicates a redshift of z = 0.63 for the lensing galaxy, and a newly-obtained Palomar spectrum indicates a redshift of z = 1.39 for the lensed source, which appears to be a galaxy. A simple single-galaxy lens model derived from the radio image reproduces the observed configuration and relative fluxes of the images, as well as the position, shape, and orientation of the lensing galaxy. Because a simple mass model is able to fit the observations, we argue that this lens system is promising for determining H_0. CLASS has also yielded the new double image lens system 1600+434. The second phase of the survey is scheduled for August and September 1995 on the VLA, and should yield images for an additional 5000+ targets, bringing the CLASS total to over 8000.

Item Type:Book Section
Related URLs:
URLURL TypeDescription ReadCube access
Fassnacht, C. D.0000-0002-4030-5461
Pearson, T. J.0000-0001-5213-6231
Readhead, A. C. S.0000-0001-9152-961X
Blandford, R. D.0000-0002-1854-5506
Djorgovski, S. G.0000-0002-0603-3087
Smith, J. D.0000-0003-1545-5078
Additional Information:© 1996 International Astronomical Union.
Subject Keywords:Radio Source; Lens System; Gravitational Lens; Relative Flux; Target Source
Series Name:International Astronomical Union Symposium (IAUS)
Issue or Number:173
Record Number:CaltechAUTHORS:20190605-134717870
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:96158
Deposited By: Tony Diaz
Deposited On:06 Jun 2019 03:30
Last Modified:19 Jan 2023 00:23

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