PHOTOMETRICALLY DERIVED MASSES AND RADII OF THE PLANET AND STAR IN THE TrES-2 SYSTEM
- NASA Ames Research Center, M/S 244-30, Moffett Field, CA 94035 (United States)
- Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
- Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom)
- Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven (Belgium)
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)
- Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States)
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
We measure the mass and radius of the star and planet in the TrES-2 system using 2.7 years of observations by the Kepler spacecraft. The light curve shows evidence for ellipsoidal variations and Doppler beaming on a period consistent with the orbital period of the planet with amplitudes of 2.79{sup +0.44}{sub -0.62} and 3.44{sup +0.32}{sub -0.37} parts per million (ppm), respectively, and a difference between the dayside and the nightside planetary flux of 3.41{sup +0.55}{sub -0.82} ppm. We present an asteroseismic analysis of solar-like oscillations on TrES-2A which we use to calculate the stellar mass of 0.94 {+-} 0.05 M{sub Sun} and radius of 0.95 {+-} 0.02 R{sub Sun }. Using these stellar parameters, a transit model fit and the phase-curve variations, we determine the planetary radius of 1.162{sup +0.020}{sub -0.024} R{sub Jup} and derive a mass for TrES-2b from the photometry of 1.44 {+-} 0.21 M{sub Jup}. The ratio of the ellipsoidal variation to the Doppler beaming amplitudes agrees to better than 2{sigma} with theoretical predications, while our measured planet mass and radius agree within 2{sigma} of previously published values based on spectroscopic radial velocity measurements. We measure a geometric albedo of 0.0136{sup +0.0022}{sub -0.0033} and an occultation (secondary eclipse) depth of 6.5{sup +1.7}{sub -1.8} ppm which we combined with the day/night planetary flux ratio to model the atmosphere of TrES-2b. We find that an atmosphere model that contains a temperature inversion is strongly preferred. We hypothesize that the Kepler bandpass probes a significantly greater atmospheric depth on the night side relative to the day side.
- OSTI ID:
- 22140040
- Journal Information:
- Astrophysical Journal, Vol. 761, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE STELLAR OBLIQUITY, PLANET MASS, AND VERY LOW ALBEDO OF QATAR-2 FROM K2 PHOTOMETRY
OPTICAL PHASE CURVES OF KEPLER EXOPLANETS