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Low Surface Brightness Radio Structure in the Field of Gravitational Lens 0957+561

I. M. Avruch·A. S. Cohen·J. Lehar·S. R. Conner·D. B. Haarsma·B. F. Burke
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Abstract

We have produced deep radio maps of the double quasar 0957+561 from multiple-epoch VLA observations. To achieve high sensitivity to extended structure we have re-reduced the best available 1.6 GHz observations and have combined 5 GHz data from multiple array configurations. Regions of faint emission approximately 15 arcsec north and south of the radio source G are probably lobes associated with the lensing galaxy. An arc 5 arcsec to the east of G may be a stretched image of emission in the background quasar's environment. 1.4 arcsec southwest of G we detect a source that we interpret as an image of emission from the quasar's western lobe, which could provide a constraint on the slope of the gravitational potential in the central region of the lens. We explore the consequences of these new constraints with simple lens models of the system.

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I. M. Avruch, A. S. Cohen, J. Lehar, S. R. Conner, D. B. Haarsma, B. F. Burke. 1997-08-19. Low Surface Brightness Radio Structure in the Field of Gravitational Lens 0957+561. https://doi.org/10.1086/310938

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