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CLASS B1555+375: A New Four-Image Gravitational Lens System

Marlow, D. R. and Myers, S. T. and Rusin, D. and Jackson, N. and Browne, I. W. A. and Wilkinson, P. N. and Muxlow, T. and Fassnacht, C. D. and Lubin, L. and Kundíc, T. and Blandford, R. D. and Pearson, T. J. and Readhead, A. C. S. and Koopmans, L. and de Bruyn, A. G. (1999) CLASS B1555+375: A New Four-Image Gravitational Lens System. Astronomical Journal, 118 (2). pp. 654-658. ISSN 0004-6256. doi:10.1086/300987.

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We have discovered a new gravitational lens in the Cosmic Lens All-Sky Survey. The lens B1555+375 is a four-image system with a maximum separation of 0.”42. VLA and MERLIN radio observations show these images in a characteristic quadruple-lens configuration. Optical imaging with the Keck II Telescope at R band shows a faint extended object. We estimate the combined emission from the lens and background source to be R = 25 mag. Observations at H band with the William Herschel Telescope also detected this extended object. The combined lens and background source magnitude was measured to be H = 19 mag. Presently, redshifts for both the lensing galaxy and background source are undetermined. We conclude that one or more of the following are true: the lens galaxy is sub-L*, it has z > 0.5, or it is highly reddened. The observed MERLIN component positions and flux densities can be well described by a lens model based on a singular isothermal ellipsoid mass distribution. Our best-fit lens model has a reduced χ^2 of 2.6. High-resolution VLA radio observations should help to constrain the lens model further.

Item Type:Article
Related URLs:
URLURL TypeDescription
Fassnacht, C. D.0000-0002-4030-5461
Blandford, R. D.0000-0002-1854-5506
Pearson, T. J.0000-0001-5213-6231
Readhead, A. C. S.0000-0001-9152-961X
Koopmans, L.0000-0003-1840-0312
Additional Information:© 1999 The American Astronomical Society. Received 1999 April 7; accepted 1999 April 29. Based on observations made with the National Radio Astronomy Observatory (NRAO), which is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. ; with the Multi-Element Radio-linked Interferometer Network (MERLIN), which is a national facility operated by the Nuffield Radio Astronomy Laboratories, Jodrell Bank, University of Manchester, on behalf of the UK Particle Physics and Astronomy Research Council; with the William Herschel Telescope (WHT), which is operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias; and with 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 Keck Observatory was made possible by the generous financial support of the W. M. Keck Foundation. We wish to thank P. J. Helbig for assistance with this work. We also thank the anonymous referee for helpful suggestions on how to improve the paper. S. T. M. is supported by an Alfred P. Sloan fellowship. This research was supported in part by the European Commission, TMR Programme, research network contract ERBFMRXCT96-0034 "CERES."
Funding AgencyGrant Number
W. M. Keck FoundationUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
Marie Curie FellowshipERBFMRXCT96-0034
Subject Keywords:gravitational lensing
Issue or Number:2
Record Number:CaltechAUTHORS:20190604-073058404
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Official Citation:D. R. Marlow et al 1999 AJ 118 654
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:96094
Deposited By: Tony Diaz
Deposited On:04 Jun 2019 18:37
Last Modified:19 Jan 2023 17:07

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