Detecting stellar spots through polarimetric observations of microlensing events in caustic-crossing

  title={Detecting stellar spots through polarimetric observations of microlensing events in caustic-crossing},
  author={Sedighe Sajadian},
  journal={Monthly Notices of the Royal Astronomical Society},
  • S. Sajadian
  • Published 28 June 2015
  • Physics, Geology
  • Monthly Notices of the Royal Astronomical Society
In this work, we investigate if gravitational microlensing can magnify the polarization signal of a stellar spot and make it be observable. A stellar spot on a source star of microlensing makes polarization signal through two channels of Zeeman effect and breaking circular symmetry of the source surface brightness due to its temperature contrast. We first explore the characteristics of perturbations in polarimetric microlensing during caustic-crossing of a binary lensing as follows: (a) The… 

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