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The third image of the large-separation lensed quasar SDSS J1029+26231

Oguri, Masamune and Ofek, Eran O. and Inada, Naohisa and Morokuma, Tomoki and Falco, Emilio E. and Kochanek, Christopher S. and Kayo, Issha and Broadhurst, Tom and Richards, Gordon T. (2008) The third image of the large-separation lensed quasar SDSS J1029+26231. Astrophysical Journal, 676 (1). L1-L4. ISSN 0004-637X.

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We identify a third image in the unique quasar lens SDSS J1029+2623, the second known quasar lens produced by a massive cluster of galaxies. The spectrum of the third image shows similar emission and absorption features but has a redder continuum than the other two images, which can be explained by differential extinction or microlensing. We also identify several lensed arcs. Our observations suggest a complicated structure of the lens cluster at z ≈ 0.6. We argue that the three lensed images are produced by a naked cusp on the basis of successful mass models, the distribution of cluster member galaxies, and the shapes and locations of the lensed arcs. Lensing by a naked cusp is quite rare among galaxy-scale lenses but is predicted to be common among large-separation lensed quasars. Thus the discovery can be viewed as support for an important theoretical prediction of the standard cold dark matter model.

Item Type:Article
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URLURL TypeDescription
Ofek, Eran O.0000-0002-6786-8774
Kochanek, Christopher S.0000-0001-6017-2961
Additional Information:© 2008 The American Astronomical Society. Received 2008 January 14; accepted 2008 January 31; published 2008 February 26. We thank Paul Schechter for useful discussions and an anonymous referee for helpful suggestions. This work was supported in part by Department of Energy contract DE-AC02- 76SF00515. C. S. K. is supported by NSF grant AST 07-08082. 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. Some of 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. This work is based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Use of the UH 2.2 m telescope for the observations is supported by NAOJ.
Funding AgencyGrant Number
Department of Energy (DOE)DE-AC02-76SF00515
NSFAST 07-08082
W. M. Keck FoundationUNSPECIFIED
National Astronomical Observatory of JapanUNSPECIFIED
Subject Keywords:galaxies: clusters: general; gravitational lensing; quasars: individual (SDSS J102913.94+262317.9)
Issue or Number:1
Record Number:CaltechAUTHORS:20090408-151706963
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:13896
Deposited By: Tony Diaz
Deposited On:17 Apr 2009 20:53
Last Modified:05 Nov 2019 00:52

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