Asteroseismic determination of obliquities of the exoplanet systems Kepler-50 and Kepler-65

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • W. J. Chaplin
  • R. Sanchis-Ojeda
  • T. L. Campante
  • R. Handberg
  • D. Stello
  • J. N. Winn
  • S. Basu
  • Jørgen Christensen-Dalsgaard
  • G. R. Davies
  • T. S. Metcalfe
  • D. A. Fischer
  • T. R. Bedding
  • W. D. Cochran
  • Y. Elsworth
  • R. L. Gilliland
  • S. Hekker
  • D. Huber
  • H. Isaacson
  • Christoffer Karoff
  • S. D. Kawaler
  • H. Kjeldsen
  • D. W. Latham
  • M. N. Lund
  • M. Lundkvist
  • G. W. Marcy
  • A. Miglio
  • T. Barclay
  • J. J. Lissauer
Results on the obliquity of exoplanet host stars - the angle between the stellar spin axis and the planetary orbital axis - provide important diagnostic information for theories describing planetary formation. Here we present the first application of asteroseismology to the problem of stellar obliquity determination in systems with transiting planets and Sun-like host stars. We consider two systems observed by the NASA Kepler mission which have multiple transiting small (super-Earth sized) planets: the previously reported Kepler-50 and a new system, Kepler-65, whose planets we validate in this paper. Both stars show rich spectra of solar-like oscillations. From the asteroseismic analysis we find that each host has its rotation axis nearly perpendicular to the line of sight with the sines of the angles constrained at the 1s level to lie above 0.97 and 0.91, respectively. We use statistical arguments to show that coplanar orbits are favored in both systems, and that the orientations of the planetary orbits and the stellar rotation axis are correlated.
OriginalsprogEngelsk
Artikelnummer101
TidsskriftThe Astrophysical Journal
Vol/bind766
Udgave nummer2
Antal sider19
ISSN0004-637X
DOI
StatusUdgivet - 1 apr. 2013

ID: 45576535