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Gravitational lensing potential reconstruction in quadruply imaged systems

V. F. Cardone·S. Capozziello·V. Re·E. Piedipalumbo
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Abstract

We develop a semi - analytical method to reconstruct the lensing potential in quadruply imaged gravitational lens systems. Assuming that the potential belongs to a broad class of boxy non - elliptical models, we show how it is possible to write down a system of equations which can be numerically solved to recover the potential parameters directly from image positions and using physical constraints. We also describe a code developed to search for solutions of the system previously found and test it on simulated cases. Finally, we apply the method to the quadruple lens PG1115+080 which allows us to get also an estimate of the Hubble constant H_0 from the measured time delay as H_0 = 56_{-11}^{+17} km/s/Mpc.

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V. F. Cardone, S. Capozziello, V. Re, E. Piedipalumbo. 2001-11-04. Gravitational lensing potential reconstruction in quadruply imaged systems. https://doi.org/10.1051/0004-6361%3A20011225

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