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Astrometric Microlensing as a Method of Discovering and Characterizing Extra-Solar Planets

Neda Safizadeh·Neal Dalal·Kim Griest
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Abstract

We introduce a new method of searching for and characterizing extra-solar planets. We show that by monitoring the center-of-light motion of microlensing alerts using the next generation of high precision astrometric instruments the probability of detecting a planet orbiting the lens is high. We show that adding astrometric information to the photometric microlensing lightcurve greatly helps in determining the planetary mass and semi-major axis. We introduce astrometric maps as a new way for calculating astrometric motion and planet detection probabilities. Finite source effects are important for low mass planets, but even Earth mass planets can give detectable signals.

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Neda Safizadeh, Neal Dalal, Kim Griest. 1998-11-14. Astrometric Microlensing as a Method of Discovering and Characterizing Extra-Solar Planets. https://doi.org/10.1086/307628

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