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Improper Motions in Lensed QSOs

L. L. R. Williams·P. Saha
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Abstract

We argue that individual images in multiple-image QSOs could easily have substructure at the level of $0.1''$ (i.e., unresolvable even with HST); microlensing within such substructure would cause centroid shifts, observable even from the ground as pseudo proper motions. We present a model of the four-image system 2237+0305 in which Image B shows such ``improper motions" of order of $0.01''$ over a few years.

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L. L. R. Williams, P. Saha. 1995-08-21. Improper Motions in Lensed QSOs. https://doi.org/10.1086/117620

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