Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions

  title={Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions},
  author={Abraham Loeb and Bologna University and Ias},
  journal={The Astrophysical Journal},
Upcoming space-based photometric satellites offer the possibility of detecting continuum flux variability at the micromagnitude (μmag) level. We show that the Doppler flux variability induced by the reflex motion of stars due to planetary companions has an amplitude of (3 - α)K/c, where K is the reflex radial velocity amplitude and α ≈ is the logarithmic slope of the source spectral flux in the observed frequency band. For many of the known close-in planetary systems with periods P 0.2 yr, the… 

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