Beware the Non-uniqueness of Einstein Rings
Astrophysics
2009-11-06 v1
Abstract
We explain how an approximation to the rings formed by the host galaxies in lensed QSOs can be inferred from the QSO data alone. A simple ring image can be made from any lens model by a simple piece of computer graphics: just plot a contour map of the arrival-time surface with closely-spaced contours. We go on to explain that rings should be (a) sensitive to time-delay ratios between different pairs of images, but (b) very insensitive to H_0. We illustrate this for the well-known quads 1115+080 and 1608+656.
Keywords
Cite
@article{arxiv.astro-ph/0104414,
title = {Beware the Non-uniqueness of Einstein Rings},
author = {Prasenjit Saha and Liliya L. R. Williams},
journal= {arXiv preprint arXiv:astro-ph/0104414},
year = {2009}
}
Comments
To appear in AJ (circa Aug 2001)