Publikationsdatum:
2019-08-26
Beschreibung:
We showed that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least 86 degrees with respect to its parent star's equatorial plane, and a strong possibility of retrograde motion. We also report evidence for an additional planet or companion star. The Rossiter-McLaughlin effect was found to be a blueshift during the first half of the transit and a redshift during the second half, an inversion of the usual pattern, implying that the angle between the sky-projected orbital and stellar angular momentum vectors is 182.5 plus or minus 9.4 degrees. The third body is implicated by excess RV variation of the host star over 2 yr. Some possible explanations for the tilted orbit of HAT-P-7b are a close encounter with another planet, the Kozai effect, and resonant capture by an inward-migrating outer planet.
Schlagwort(e):
Astrophysics
Materialart:
Astrophysical Journal Letters; 703; 2; L99-L103
Format:
text
Permalink
