Finite Source Effects in Microlensing Events
نویسنده
چکیده
The computation of the magnification of a finite source by an arbitrary gravitational lens can be reduced from a two-dimensional to a one-dimensional integral using a generalization of Stoke’s theorem. For a large source lensed by a planetarysystem whose planet lies at the position where one of the two images would be in the absence of a planet, the integral can be done analytically. If the planet lies at the position of the major (unperturbed) image, the excess flux is the same as it would be for an isolated planet. If the planet lies at the minor image, there is no excess flux. Subject Headings: gravitational lensing – methods: numerical – planetary systems Submitted to The Astrophysical Journal Letters June 17, 1996 Preprint: OSU-TA-17/96 1 Alfred P. Sloan Foundation Fellow
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