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Uncovering stellar atmospheres with gravitational microlensing telescopes

M. Dominik
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Abstract

A strong differential magnification over the face of the source star passing the caustic created by a binary lens star allows to measure its radial intensity profile with an angular resolution of 20-60 nas from broad-band photometric observations for ~15 stars per year and to study its chemical composition from time-resolved high-resolution spectroscopy for ~2 stars per year.

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M. Dominik. 2003-12-08. Uncovering stellar atmospheres with gravitational microlensing telescopes. https://arxiv.org/abs/astro-ph/0312200

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