Probability of Detecting a Planetary Companion during a Microlensing Event

  title={Probability of Detecting a Planetary Companion during a Microlensing Event},
  author={Stanton J. Peale},
  journal={The Astrophysical Journal},
  pages={889 - 911}
  • S. Peale
  • Published 18 January 2001
  • Physics, Geology
  • The Astrophysical Journal
The averaged probability of detecting a planetary companion of a lensing star during a microlensing event toward the Galactic center when the planet to star mass ratio q = 0.001 is shown to have a maximum exceeding 10% at an orbit semimajor axis near 1.5 AU for a uniform distribution of impact parameters. This peak value is somewhat lower than the maximum of 17% obtained by Gould & Loeb in 1992, but it is raised to more than 20% for a distribution of source-lens impact parameters that is… 

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