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The External Shear Acting on Gravitational Lens B1422+231

Kundić, Tomislav and Hogg, David W. and Blandford, Roger D. and Cohen, Judith G. and Lubin, Lori M. and Larkin, James E. (1997) The External Shear Acting on Gravitational Lens B1422+231. Astronomical Journal, 114 (6). pp. 2276-2283. ISSN 0004-6256. doi:10.1086/118647.

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In a number of multiply imaged quasar systems, a significant contribution to the lensing potential is provided by groups and clusters of galaxies associated with the primary lens. As part of an ongoing effort to gather observational data on these systems, we present spectroscopy and near-infrared and optical photometry of galaxies in the field of the quadruple lens system B1422+231. The spectra show that the primary lens and five nearby galaxies belong to a compact group at ζ=0.338. The median projected radius of this group is 35h^(-1) kpc and its velocity dispersion is ˜550 km s^(-1). A straightforward application of the virial theorem yields a group mass of 1.4X10^(13)h^(-1) M⊙, which provides sufficient external shear to produce the observed image configuration. This data rules out a class of models and improves the system's prospects for a measurement of the Hubble constant.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hogg, David W.0000-0003-2866-9403
Blandford, Roger D.0000-0002-1854-5506
Cohen, Judith G.0000-0002-8039-4673
Larkin, James E.0000-0001-7687-3965
Additional Information:© 1997 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1997 June 17; revised 1997 September 7; accepted 1997 September 10. Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the California Institute of Technology and the University of California. We are grateful to the W. M. Keck Foundation for the vision to fund the construction of the W. M. Keck Observatory. We thank Charles Lawrence, Keith Matthews, Gerry Neugebauer, and Tom Soifer for making their unpublished near-infrared data available. We benefited from helpful conversations with Sangeeta Malhotra and Michael Fahre. Financial support was provided by NSF Grants No. AST-92-23370 and No. AST 95-29170, and by NASA Grant No. NAG-5-3834. This research made use of NASA’s Astrophysics Data System Abstract Service.
Funding AgencyGrant Number
W. M. Keck FoundationUNSPECIFIED
NSFAST 92-23370
NSFAST 95-29170
NASANAG 5-3834
Issue or Number:6
Record Number:CaltechAUTHORS:20190529-100450801
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ID Code:95846
Deposited By: Tony Diaz
Deposited On:29 May 2019 19:34
Last Modified:16 Nov 2021 17:16

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