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Determination of time delay from the gravitational lens B1422+231

A. R. Patnaik·D. Narasimha
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Abstract

We present the radio light curves of lensed images of the gravitational lens B1422+231. The observations have been carried out using the VLA at 8.4 and 15 GHz over a period of 197 days. We describe a method to estimate the time delay from the observed light curves. Using this method, our cross-correlation analysis shows that the time delay between images B and A is 1.5$\pm$1.4d, between A and C is 7.6$\pm$2.5d, between B and C is 8.2$\pm$2.0d. When applied to other lensed systems with measured time delays our new method gives comparable results.

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A. R. Patnaik, D. Narasimha. 2001-06-06. Determination of time delay from the gravitational lens B1422+231. https://doi.org/10.1111/j.1365-2966.2001.04711.x

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