Spectral Line Distortions in the Presence of a Close-In Planet

Abstract

We discuss the interpretation of distortions to stellar spectral lines with particular attention to line bisectors in the presence of an orbiting planetary companion. We present a simple model whereby light reflected by the companion can cause temporal variations to the observed line profiles. These distortions have a characteristic signature depending on the inclination angle of the system. For the known close-in extrasolar giant planets, the expected amplitude of the effect might not be far from current detection capabilities. This method could be used to directly detect the presence of the companion, yielding the orbital inclination and hence the planetary mass. Futhermore, a detection would measure a combination of the planetary radius and albedo, from which a minimum radius may be deduced.

8 pages, 4 figures, uses emulateapj.sty, accepted by ApJ Letters

References in corpus (5)

• Extrasolar Giant Planets under Strong Stellar Irradiation
• Further evidence for the planet around 51 Pegasi
• A Search for Line Shape and Depth Variations in 51 Pegasi and Tau Bootis
• Exoplanets or Dynamic Atmospheres? The Radial Velocity and Line Shape Variations of 51 Pegasi and Tau Bootis
• A Search for Variability in the Spectral Line Shapes of tau Bootis: Does this Star Really Have a Planet?

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• Extra-Solar Planets
• Discovery of water at high spectral resolution in the atmosphere of 51 Peg b
• Probable detection of starlight reflected from the giant exoplanet orbiting tau Bootis
• Arid or Cloudy: Characterizing the Atmosphere of the super-Earth 55 Cancri e using High-Resolution Spectroscopy
• Direct detection and characterization of M-dwarf planets using light echoes