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2016+112: a gravitationally lensed type II quasar

Koopmans, L. V. E. and Garrett, M. A. and Blandford, R. D. and Lawrence, C. R. and Patnaik, A. R. and Porcas, R. W. (2002) 2016+112: a gravitationally lensed type II quasar. Monthly Notices of the Royal Astronomical Society, 334 (1). pp. 39-47. ISSN 0035-8711.

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A single-screen model of the gravitational lens system 2016+112 is proposed, that explains recent Hubble Space Telescope (HST) infrared (NICMOS–F160W) observations and new high-resolution European VLBI Network (EVN) 5-GHz radio observations, presented in this paper. In particular, we find that a massive ‘dark’ structure at the lens position, previously suggested by X-ray, optical and spectroscopic observations of the field around 2016+112, is not necessarily required to accommodate the strong-lensing constraints. A massive structure to the north-west of the lens system, suggested from a weak-lensing analysis of the field, is included in the model. The lensed source is an X-ray bright active galaxy at z= 3.273 with a central bright optical continuum core and strong narrow emission lines, suggestive of a type II quasar. The EVN 5-GHz radio maps show a radio jet structure with at least two compact subcomponents. We propose that the diamond caustic crosses the counter-jet of the radio source, so that part of the counter-jet, host galaxy and narrow-line emission regions are quadruply imaged. The remainder of the radio source, including the core, is doubly imaged. Our lens model predicts a very high magnification (μ∼ 300) at the brightness peaks of the inner two radio components of complex C. If the jet exhibits relativistic velocities on microarsecond scales, it might result in apparent hyperluminal motion. However, the lack of strong radio variability and the peaked radio spectrum imply that these motions need not be present in the source. Our model furthermore implies that the optical spectrum of C′ can only show features of the active galactic nuclei and its host galaxy.

Item Type:Article
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URLURL TypeDescription Paper
Koopmans, L. V. E.0000-0003-1840-0312
Blandford, R. D.0000-0002-1854-5506
Additional Information:© 2002 RAS. Accepted 2002 February 13. Received 2002 January 3; in original form 2001 July 13. The European VLBI Network is a joint facility of European and Chinese radio astronomy institutes funded by their national research councils. LVEK and RDB would like to thank Ian Browne for invaluable help during the initial phases of this research. We thank Ian Browne and Sunita Nair for useful comments on a draft of the paper. LVEK thanks Eric Agol for stimulating discussions and George Chartas for sending a version of their paper on Chandra X-ray observations of 2016+112 prior to publication. This research has been supported by NSF AST-9900866 and STScI GO-06543.03-95A.
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Subject Keywords:gravitational lensing, quasars: general, radio continuum: general
Issue or Number:1
Record Number:CaltechAUTHORS:20190523-125438126
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Official Citation:L. V. E. Koopmans, M. A. Garrett, R. D. Blandford, C. R. Lawrence, A. R. Patnaik, R. W. Porcas, 2016+112: a gravitationally lensed type II quasar, Monthly Notices of the Royal Astronomical Society, Volume 334, Issue 1, 21 July 2002, Pages 39–47,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95748
Deposited By: George Porter
Deposited On:24 May 2019 14:16
Last Modified:03 Oct 2019 21:16

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