Perturbative approach to the astrometric microlensing due to an extrasolar planet

Abstract

We have developed a perturbative approach to microlensing due to an extrasolar planetary lens. In particular, we have found analytic formulae for triple images. We have used the formulae to investigate the astrometric microlensing due to the extrasolar planetary lens, in expectation of dramatic improvements in the precision of the future astrometric measurements. For a weak lensing case, we have shown how the maximum angular size and the typical time scale of the anomalous shift of the lightcentroid are dependent on the mass ratio and angular separation between the star and the planet.

11 pages (LaTeX); accepted for publication in Astrophys. J

References in corpus (1)

• Properties of Planet-induced Deviations in the Astrometric Microlensing Centroid Shift Trajectory

Cited by in corpus (11)

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• Astrometric Image Centroid Displacements due to Gravitational Microlensing by the Ellis Wormhole
• Properties of Central Caustics in Planetary Microlensing
• A Characteristic Planetary Feature in Double-Peaked, High-Magnification Microlensing Events
• Analysis of Microlensing Light Curves Induced by Multiple-Planet Systems
• Microlensed image centroid motions by an exotic lens object with negative convergence or negative mass
• Gravitational lensing by exotic objects
• A public code for astrometric microlensing with contour integration
• Parallax and orbital effects in astrometric microlensing with binary sources
• Astrometric microlensing
• Perturbation theory of N point-mass gravitational lens systems without symmetry: small mass-ratio approximation