2009/10/12 by Andrew Gould, Subo Dong, David P. Bennett +3 · 1 citation
Physics and Astronomy · #astro-ph.EP #astro-ph.IM
paper · pdf · doi:10.1088/0004-637x/710/2/1800
published as Astrophys.J.710:1800-1805,2010 · 16 pages including 3 figures. Submitted to ApJ
arxiv created 2009/10/12 · arxiv updated 2014/11/20
At present, microlensing light curves from different telescopes and filters are photometrically aligned by fitting them to a common model. We present a second method based on photometry of common field stars. If two spectral responses are similar (or the color of the source is known) then this technique can resolve important ambiguities that frequently arise when predicting the future course of the event, and that occasionally persist even when the event is over. Or if the spectral responses are different, it can be used to derive the color of the source when that is unknown. We present the essential elements of this technique and apply it to the case of MOA-2007-BLG-192, an important planetary event for which the system may be a terrestrial planet orbiting a brown dwarf or very low mass star. The refined estimate of the source color that we derive here, V-I=2.36 +- 0.03, will aid in making the estimate of the lens mass more precise.