Analysis of selected Kepler Mission planetary light curves

Abstract

We have modified the graphical user interfaced close binary system analysis program CurveFit to the form WinKepler and applied it to 16 representative planetary candidate light curves found in the NASA Exoplanet Archive (NEA) at the Caltech website http://exoplanetarchive.ipac.caltech.edu, with an aim to compare different analytical approaches. WinKepler has parameter options for a realistic physical model, including gravity-brightening and structural parameters derived from the relevant Radau equation. We tested our best-fitting parameter-sets for formal determinacy and adequacy. A primary aim is to compare our parameters with those listed in the NEA. Although there are trends of agreement, small differences in the main parameter values are found in some cases, and there may be some relative bias towards a 90 degrees value for the NEA inclinations. These are assessed against realistic error estimates. Photometric variability from causes other than planetary transits affects at least 6 of the data-sets studied; with small pulsational behaviour found in 3 of those. For the false positive KOI 4.01, we found that the eclipses could be modelled by a faint background classical Algol as effectively as by a transiting exoplanet. Our empirical checks of limb-darkening, in the cases of KOI 1.01 and 12.01, revealed that the assigned stellar temperatures are probably incorrect. For KOI 13.01, our empirical mass-ratio differs by about 7% from that of Mislis and Hodgkin (2012), who neglected structural effects and higher order terms in the tidal distortion. Such detailed parameter evaluation, additional to the usual main geometric ones, provides an additional objective for this work.

arXiv commentAccepted for publication in Astrophysics and Space Science

References in corpus (20)

• Analytic Lightcurves for Planetary Transit Searches
• Planetary Candidates Observed by Kepler, III: Analysis of the First 16 Months of Data
• Characteristics of planetary candidates observed by Kepler, II: Analysis of the first four months of data
• On the Unique Solution of Planet and Star Parameters from an Extrasolar Planet Transit Light Curve
• Kepler Input Catalog: Photometric Calibration and Stellar Classification
• HAT-P-11b: A Super-Neptune Planet Transiting a Bright K Star in the Kepler Field
• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• A Revised Effective Temperature Scale for the Kepler Input Catalog
• Modeling Kepler transit light curves as false positives: Rejection of blend scenarios for Kepler-9, and validation of Kepler-9d, a super-Earth-size planet in a multiple system
• Kepler Mission Stellar and Instrument Noise Properties
• HAT-P-7b: An Extremely Hot Massive Planet Transiting a Bright Star in the Kepler Field
• System description and first light-curves of HAT, an autonomous observatory for variability search
• Identification of Background False Positives from Kepler Data
• The Discovery of Ellipsoidal Variations in the Kepler Light Curve of HAT-P-7
• Characterizing the Cool Kepler Objects of Interest. New Effective Temperatures, Metallicities, Masses and Radii of Low-Mass Kepler Planet-Candidate Host Stars
• Binarity of Transit Host Stars - Implications on Planetary Parameters
• An Independent Analysis of Kepler-4b through Kepler-8b
• Kepler KOI-13.01 - Detection of beaming and ellipsoidal modulations pointing to a massive hot Jupiter
• SOPHIE velocimetry of Kepler transit candidates VI. An additional companion in the KOI-13 system
• A massive exoplanet candidate around KOI-13: Independent confirmation by ellipsoidal variations

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• Analysis of the exoplanet containing system Kepler 91
• An Investigation into Exoplanet Transits and Uncertainties
• Transit modelling of selected Kepler systems
• Exoplanet System Kepler-2 with comparisons to Kepler-1 and 13