THE DISCOVERY OF ELLIPSOIDAL VARIATIONS IN THE KEPLER LIGHT CURVE OF HAT-P-7

2010/01/31 by William F. Welsh, Jerome A. Orosz, Sara Seager +7 · 7 citations
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Kepler #Light curve #Occultation #Orbit (dynamics) #Physics #Planet #Star (game theory) #Stellar, planetary, and galactic studies #Transit (satellite) #astro-ph.EP #astro-ph.SR

paper · pdf · doi:10.1088/2041-8205/713/2/l145

8 pages, 3 figures, 1 table; Accepted by ApJL on 2010 Feb 4. Revision contains minor corrections and updates to references, affiliation, acknowledgments, etc.

arxiv created 2010/02/05 · openalex publication_date 2010/03/31 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We present an analysis of the early Kepler observations of the previously discovered transiting planet HAT-P-7b. The light curve shows the transit of the star, the occultation of the planet, and the orbit phase-dependent light from the planet. In addition, phase-dependent light from the star is present, known as "ellipsoidal variations." The very nearby planet (only four stellar radii away) gravitationally distorts the star and results in a flux modulation twice per orbit. The ellipsoidal variations can confuse interpretation of the planetary phase curve if not self-consistently included in the modeling. We fit the light curve using the Roche potential approximation and derive improved planet and orbit parameters.

Citations

• ASTEROSEISMIC INVESTIGATION OF KNOWN PLANET HOSTS IN THE KEPLER FIELD
• INITIAL CHARACTERISTICS OF KEPLER LONG CADENCE DATA FOR DETECTING TRANSITING PLANETS
• On the Selection of Photometric Planetary Transits
• KEPLER MISSION DESIGN, REALIZED PHOTOMETRIC PERFORMANCE, AND EARLY SCIENCE
• The secondary eclipse of the transiting exoplanet CoRoT-2b
• Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions
• A map of the day–night contrast of the extrasolar planet HD 189733b
• On the Dayside Thermal Emission of Hot Jupiters

Cited by

• Distinguishing between stellar and planetary companions with phase monitoring
• THE ATMOSPHERIC CIRCULATION AND OBSERVABLE PROPERTIES OF NON-SYNCHRONOUSLY ROTATING HOT JUPITERS
• PHOTOMETRICALLY DERIVED MASSES AND RADII OF THE PLANET AND STAR IN THE TrES-2 SYSTEM
• Detection of visible light from the darkest world
• Fourier spectra from exoplanets with polar caps and ocean glint
• Detecting the signatures of Uranus and Neptune
• THE DEEP BLUE COLOR OF HD 189733b: ALBEDO MEASUREMENTS WITH HUBBLE SPACE TELESCOPE /SPACE TELESCOPE IMAGING SPECTROGRAPH AT VISIBLE WAVELENGTHS

Related

• Planet influence on the shape of the hosting star - ellipsoidal variations of tau Bootis
• Transiting planets - light-curve analysis for eccentric orbits
• Sun flux variation due to the effects of orbiting planets. Case of study of a non-compact planetary system
• Eccentricity is Not Responsible for Odd Harmonics in HAT-P-7 and Kepler-13A
• A General, Differentiable Transit Model for Ellipsoidal Occulters: Derivation, Application, and Forecast of Planetary Oblateness and Obliquity Constraints with JWST