Details

Autor(en) / Beteiligte

• Barclay, Thomas
• Huber, Daniel
• Rowe, Jason F
• tney, Jonathan J
• Morley, Caroline V
• Quintana, Elisa V
• Fabrycky, Daniel C
• BARENTSEN, GEERT
• Bloemen, Steven
• Christiansen, Jessie L

Titel

PHOTOMETRICALLY DERIVED MASSES AND RADII OF THE PLANET AND STAR IN THE TrES-2 SYSTEM

Ist Teil von

• The Astrophysical journal, 2012-12, Vol.761 (1), p.1-10

Ort / Verlag

United States

Erscheinungsjahr

2012

Quelle

EZB-FREE-00999 freely available EZB journals

Beschreibungen/Notizen

• 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 super(+0.44) sub(-0.62) and 3.44 super(+0.32) sub(-0.37) parts per million (ppm), respectively, and a difference between the dayside and the nightside planetary flux of 3.41 super(+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 + or - 0.05 M sub([middot in circle]) and radius of 0.95 + or - 0.02 R sub([middot in circle]). Using these stellar parameters, a transit model fit and the phase-curve variations, we determine the planetary radius of 1.162 super(+0.020) sub(-0.024) R sub(Jup) and derive a mass for TrES-2b from the photometry of 1.44 + or - 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 super(+0.0022) sub(-0.0033) and an occultation (secondary eclipse) depth of 6.5 super(+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.