KELT-7b: A HOT JUPITER TRANSITING A BRIGHT V=8.54 RAPIDLY ROTATING F-STAR Academic Article uri icon

abstract

  • 2015. The American Astronomical Society. All rights reserved. We report the discovery of KELT-7b, a transiting hot Jupiter with a mass of 1.28 0.18MJ, radius of 1.533 0.0470.046RJ, and an orbital period of 2.7347749 0.0000039 days. The bright host star (HD 33643; KELT-7) is an F-star with V = 8.54, Teff= 6789 4950 K, [Fe/H] 0.139 0.081 = -0.075, and log g = 4.149 0.019. It has a mass of 1.535 0.0540.066 Me, a radius of 1.732 0.0450.043 Re, and is the fifth most massive, fifth hottest, and the ninth brightest star known to host a transiting planet. It is also the brightest star around which Kilodegree Extremely Little Telescope (KELT) has discovered a transiting planet. Thus, KELT-7b is an ideal target for detailed characterization given its relatively low surface gravity, high equilibrium temperature, and bright host star. The rapid rotation of the star (73 0.5 km s-1) results in a RossiterMcLaughlin effect with an unusually large amplitude of several hundred m s-1. We find that the orbit normal of the planet is likely to be well-aligned with the stellar spin axis, with a projected spin orbit alignment of = 9.7 5. 2. This is currently the second most rapidly rotating star to have a reflex signal (and thus mass determination) due to a planetary companion measured.

published proceedings

  • ASTRONOMICAL JOURNAL

altmetric score

  • 4.25

author list (cited authors)

  • Bieryla, A., Collins, K., Beatty, T. G., Eastman, J., Siverd, R. J., Pepper, J., ... Trueblood, P.

citation count

  • 67

complete list of authors

  • Bieryla, Allyson||Collins, Karen||Beatty, Thomas G||Eastman, Jason||Siverd, Robert J||Pepper, Joshua||Gaudi, B Scott||Stassun, Keivan G||Canas, Caleb||Latham, David W||Buchhave, Lars A||Sanchis-Ojeda, Roberto||Winn, Joshua N||Jensen, Eric LN||Kielkopf, John F||McLeod, Kim K||Gregorio, Joao||Colon, Knicole D||Street, Rachel||Ross, Rachel||Penny, Matthew||Mellon, Samuel N||Oberst, Thomas E||Fulton, Benjamin J||Wang, Ji||Berlind, Perry||Calkins, Michael L||Esquerdo, Gilbert A||DePoy, Darren L||Gould, Andrew||Marshall, Jennifer||Pogge, Richard||Trueblood, Mark||Trueblood, Patricia

publication date

  • July 2015