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QSO 0957+561 and other large-separated double quasars: some new results and a future observational project

V. L. Oknyanskij
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Abstract

We collected from literature the information about large-separated pairs of QSOs, which however once were suspected as gravitationally lensed system. We discuss some new results on time delay determinations including optical-radio correlations for QSO 0957+561. We considered some possible observational effects of gravitational lensing by a cosmic string. A future international project for observations of the gravitational lens system UM425 is briefly discussed.

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V. L. Oknyanskij. 2005-02-14. QSO 0957+561 and other large-separated double quasars: some new results and a future observational project. https://arxiv.org/abs/astro-ph/0502087

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