Expectations on mass determination using astrometric microlensing by Gaia

  title={Expectations on mass determination using astrometric microlensing by Gaia},
  author={J. Kluter and Ulrich Bastian and Joachim Wambsganss},
  journal={arXiv: Instrumentation and Methods for Astrophysics},
Context. Astrometric gravitational microlensing can be used to determine the mass of a single star (the lens) with an accuracy of a few percent. To do so, precise measurements of the angular separations between lens and background star with an accuracy below 1 milli-arcsecond at different epochs are needed. Hence only the most accurate instruments can be used. However, since the timescale is in the order of months to years, the astrometric deflection might be detected by Gaia, even though each… 

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