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A new quadruple gravitational lens system: CLASS B0128+437

Phillips, P. M. and Norbury, M. A. and Koopmans, L. V. E. and Browne, I. W. A. and Jackson, N. J. and Wilkinson, P. N. and Biggs, A. D. and Blandford, R. D. and de Bruyn, A. G. and Fassnacht, C. D. and Helbig, P. and Mao, S. and Marlow, D. R. and Myers, S. T. and Pearson, T. J. and Readhead, A. C. S. and Rusin, D. and Xanthopoulos, E. (2000) A new quadruple gravitational lens system: CLASS B0128+437. Monthly Notices of the Royal Astronomical Society, 319 (2). L7-L11. ISSN 0035-8711.

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High-resolution MERLIN observations of a newly discovered four-image gravitational lens system, B0128+437, are presented. The system was found after a careful re-analysis of the entire CLASS data set. The MERLIN observations resolve four components in a characteristic quadruple-image configuration; the maximum image separation is 542 mas and the total flux density is 48 mJy at 5 GHz. A best-fitting lens model with a singular isothermal ellipsoid results in large errors in the image positions. A significantly improved fit is obtained after the addition of a shear component, suggesting that the lensing system is more complex and may consist of multiple deflectors. The integrated radio spectrum of the background source indicates that it is a gigahertz peaked spectrum source. It may therefore be possible to resolve structure within the radio images with deep VLBI observations and thus to constrain the lensing mass distribution better.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Koopmans, L. V. E.0000-0003-1840-0312
Biggs, A. D.0000-0002-1117-9961
Blandford, R. D.0000-0002-1854-5506
Fassnacht, C. D.0000-0002-4030-5461
Mao, S.0000-0001-8317-2788
Pearson, T. J.0000-0001-5213-6231
Readhead, A. C. S.0000-0001-9152-961X
Additional Information:© 2000 RAS. Accepted 2000 September 18. Received 2000 August 30; in original form 2000 June 28. The Very Large Array is operated by the National Radio Astronomy Observatory which is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. MERLIN is the Multi-Element Radio Linked Interferometer Network and is a national facility operated by the University of Manchester on behalf of PPARC. This research was supported in part by the European Commission, TMR Programme, Research Network Contract ERBFMRXCT96-0034 ‘CERES’. PMP also thanks PPARC for the support of a studentship award.
Funding AgencyGrant Number
Particle Physics and Astronomy Research Council (PPARC)UNSPECIFIED
Marie Curie FellowshipERBFMRXCT96-0034
Subject Keywords:quasars: individual: B0128+437, cosmology: observations, gravitational lensing
Issue or Number:2
Record Number:CaltechAUTHORS:20190523-125438233
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Official Citation:P. M. Phillips, M. A. Norbury, L. V. E. Koopmans, I. W. A. Browne, N. J. Jackson, P. N. Wilkinson, A. D. Biggs, R. D. Blandford, A. G. de Bruyn, C. D. Fassnacht, P. Helbig, S. Mao, D. R. Marlow, S. T. Myers, T. J. Pearson, A. C. S. Readhead, D. Rusin, E. Xanthopoulos, A new quadruple gravitational lens system: CLASS B0128+437, Monthly Notices of the Royal Astronomical Society, Volume 319, Issue 2, 1 December 2000, Pages L7–L11,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95749
Deposited By: George Porter
Deposited On:24 May 2019 14:18
Last Modified:03 Oct 2019 21:16

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