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Galaxy Groups Associated with Gravitational Lenses and H_0 from B1608+656

Fassnacht, Chris and Lubin, Lori and Mckean, John and Gal, Roy and Squires, Gordon and Koopmans, Leon and Treu, Tommaso and Blandford, Roger and Rusin, David (2005) Galaxy Groups Associated with Gravitational Lenses and H_0 from B1608+656. In: Impact of Gravitational Lensing in Cosmology. IAU Symposia. No.225. Cambridge University Press , Cambridge, pp. 311-316. ISBN 978-0-521-85196-1.

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Compact groups of galaxies recently have been discovered in association with several strong gravitational lens systems. These groups provide additional convergence to the lensing potential and thus affect the value of H_0 derived from the systems. Lens system time delays are now being measured with uncertainties of only a few percent or better. Additionally, vast improvements are being made in incorporating observational constraints such as Einstein ring structures and stellar velocity dispersions into the lens models. These advances are reducing the uncertainties on H_0 to levels at which the the effects of associated galaxy groups may contribute significantly to the overall error budget. We describe a dedicated multiwavelength program, using Keck, HST, and Chandra, to find such groups and measure their properties. We present, as a case study, results obtained from observations of the CLASS lens system B1608+656 and discuss the implications for the value of H_0 derived from this system.

Item Type:Book Section
Related URLs:
URLURL TypeDescription DOIArticle
Treu, Tommaso0000-0002-8460-0390
Blandford, Roger0000-0002-1854-5506
Additional Information:© 2004 International Astronomical Union. Published online: 15 June 2005.
Series Name:IAU Symposia
Issue or Number:225
Record Number:CaltechAUTHORS:20111012-102853216
Persistent URL:
Official Citation:Galaxy Groups Associated with Gravitational Lenses and H_0 from B1608+656 Chris Fassnacht, Lori Lubin, John McKean, Roy Gal, Gordon Squires, Leon Koopmans, Tommaso Treu, Roger Blandford and David Rusin Proceedings of the International Astronomical Union. Volume 2004 Issue IAUS225, pp 311 - 317 2004 International Astronomical Union Published online: 15 June 2005 DOI:10.1017/S1743921305002115
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:27184
Deposited By: Ruth Sustaita
Deposited On:12 Oct 2011 18:24
Last Modified:09 Nov 2021 16:46

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