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arXiv · astro-ph/0303261

Qualitative Theory for Lensed QSOs

Prasenjit Saha·Liliya L. R. Williams
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Abstract

We show that some characteristics of multiply-imaged QSO systems are very model-independent and can be deduced accurately by simply scrutinizing the relative positions of images and galaxy-lens center. These include the time-ordering of the images, the orientation of the lens potential, and the rough morphology of any ring. Other features can differ considerably between specific models; H_0 is an example. Surprisingly, properties inherited from a circularly symmetric lens system are model-dependent, whereas features that arise from the breaking of circular symmetry are model-independent. We first develop these results from some abstract geometrical ideas, then illustrate them for some well-known systems (the quads Q2237+030, H1413+117, HST14113+5211, PG1115+080, MG0414+0534, B1608+656, B1422+231, and RXJ0911+0551, and the ten-image system B1933+507), and finally remark on two systems (B1359+154 and PMN J0134-0931) where the lens properties are more complex. We also introduce a Java applet which produces simple lens systems, and helps further illustrate the concepts.

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Prasenjit Saha, Liliya L. R. Williams. 2003-03-12. Qualitative Theory for Lensed QSOs. https://doi.org/10.1086/375204

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