We use high-resolution adaptive optics (AO) imaging on the Keck II telescope to study the gravitational lens B0128+437 in unprecedented detail, allowing us to resolve individual lensed quasar components and, for the first time, detect and measure properties of the lensing galaxy. B0128+437 is a small separation lens with known flux-ratio and astrometric anomalies. We discuss possible causes for these anomalies, including the presence of substructure in the lensing galaxy, propagation effects due to dust and a turbulent interstellar medium, and gravitational microlensing. This work on B0128 demonstrates that AO will be an essential tool for studying the many new small-separation lenses expected from future surveys.
@article{arxiv.0912.2344,
title = {Adaptive Optics Observations of B0128+437: A Low-Mass, High-Redshift Gravitational Lens},
author = {David J. Lagattuta and Matthew W. Auger and Christopher D. Fassnacht},
journal= {arXiv preprint arXiv:0912.2344},
year = {2015}
}
Comments
5 pages, 2 figure, updated to version accepted by ApJ Letters