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Keck spectroscopy of Cosmic Lens All-Sky Survey gravitational lenses

McKean, J. P. and Koopmans, L. V. E. and Browne, I. W. A. and Fassnacht, C. D. and Blandford, R. D. and Lubin, L. M. and Readhead, A. C. S. (2004) Keck spectroscopy of Cosmic Lens All-Sky Survey gravitational lenses. Monthly Notices of the Royal Astronomical Society, 350 (1). pp. 167-174. ISSN 0035-8711. doi:10.1111/j.1365-2966.2004.07630.x.

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We present the optical spectra of four newly discovered gravitational lenses from the Cosmic Lens All‐Sky Survey (CLASS). These observations were carried out using the Low‐Resolution Imaging Spectrograph on the W. M. Keck‐I Telescope as part of a programme to study galaxy‐scale gravitational lenses. From our spectra, we found the redshift of the background source in CLASS B0128+437 (z_s= 3.1240 ± 0.0042) and the lensing galaxy redshifts in CLASS B0445+123 (z_1= 0.5583 ± 0.0003) and CLASS B0850+054 (z_l= 0.5883 ± 0.0006). Intriguingly, we also discovered that CLASS B0631+519 may have two lensing galaxies (zl,1= 0.0896 ± 0.0001, z_(l,2)= 0.6196 ± 0.0004). We also found a single unidentified emission line from the lensing galaxy in CLASS B0128+437 and the lensed source in CLASS B0850+054. We find the lensing galaxies in CLASS B0445+123 and CLASS B0631+519 (l, 2) to be early‐type galaxies with Einstein radii of 2.8–3.0 h^(−1) kpc. The deflector in CLASS B0850+054 is a late‐type galaxy with an Einstein radius of 1.6 h^(−1) kpc.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Koopmans, L. V. E.0000-0003-1840-0312
Fassnacht, C. D.0000-0002-4030-5461
Blandford, R. D.0000-0002-1854-5506
Readhead, A. C. S.0000-0001-9152-961X
Alternate Title:Keck spectroscopy of CLASS gravitational lenses
Additional Information:© 2004 RAS. Accepted 2004 January 14. Received 2004 January 13; in original form 2003 December 2. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has made use of the NASA/IPAC Extragalactic Data base (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. JPM acknowledges the receipt of a PPARC studentship. LVEK acknowledges the support from an STScI Fellowship grant. RDB is supported by NSF grant AST–0206286.
Funding AgencyGrant Number
W. M. Keck FoundationUNSPECIFIED
Particle Physics and Astronomy Research Council (PPARC)UNSPECIFIED
Space Telescope Science InstituteUNSPECIFIED
Subject Keywords:gravitational lensing, quasars: individual: CLASS B0128+437, quasars: individual: CLASS B0445+123, quasars: individual: CLASS B0631+519, quasars: individual: CLASS B0850+054
Issue or Number:1
Record Number:CaltechAUTHORS:20190523-125437551
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Official Citation:J. P. McKean, L. V. E. Koopmans, I. W. A. Browne, C. D. Fassnacht, R. D. Blandford, L. M. Lubin, A. C. S. Readhead, Keck spectroscopy of Cosmic Lens All‐Sky Survey gravitational lenses, Monthly Notices of the Royal Astronomical Society, Volume 350, Issue 1, 1 May 2004, Pages 167–174,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95743
Deposited By: George Porter
Deposited On:23 May 2019 23:00
Last Modified:16 Nov 2021 17:15

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