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arXiv · 0912.2344

Adaptive Optics Observations of B0128+437: A Low-Mass, High-Redshift Gravitational Lens

David J. Lagattuta·Matthew W. Auger·Christopher D. Fassnacht
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Abstract

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.

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David J. Lagattuta, Matthew W. Auger, Christopher D. Fassnacht. 2010-06-08. Adaptive Optics Observations of B0128+437: A Low-Mass, High-Redshift Gravitational Lens. https://doi.org/10.1088/2041-8205%2F716%2F2%2Fl185

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