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arXiv · astro-ph/9601093

Deep radio observation of the gravitational lens candidate QSO2345+007

Alok R. Patnaik·Peter Schneider·Ramesh Narayan
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Abstract

The double QSO2345+007 comprises two optical components separated by 7.1\ arcseconds and is the most prominent `dark matter' gravitational lens candidate. Despite being known for more than a decade, optical spectroscopy and imaging have been unable to determine whether this double QSO is a binary QSO or a gravitational lens system. In this note we report a deep VLA observation of this system, yielding a map with a noise level of 8.5\ts $μ$Jy per beam. We have a $4σ$ detection of a radio source within one arcsecond of the optical position of the brighter A-component of the QSO, but no significant detection of any radio counterpart of the B component. Given that the flux ratio in the optical waveband is $\sim$3--4, the gravitational lens hypothesis for this system would predict a radio flux of image B of $\lesssim 10$\ts $μ$Jy. The non-detection of the B component is thus consistent with, but does not prove, the lens interpretation.

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Alok R. Patnaik, Peter Schneider, Ramesh Narayan. 1996-01-18. Deep radio observation of the gravitational lens candidate QSO2345+007. https://doi.org/10.1093/mnras%2F281.2.l17

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