ar X iv : a st ro - p h / 02 06 22 8 v 1 1 3 Ju n 20 02 On the Unique Solution of Planet and Star Parameters from an Extrasolar Planet Transit Light Curve
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چکیده
There is a unique solution of the planet and star parameters from a planet transit light curve with two or more transits if the planet has a circular orbit and the light curve is observed in a band pass where limb darkening is negligible. The existence of this unique solution is very useful for current planet transit surveys for several reasons. First, there is an analytic solution that allows a quick parameter estimate, in particular of R p. Second, the stellar density can be uniquely derived from the transit light curve alone. The stellar density can be used to immediately rule out a giant star (and hence a much larger than planetary companion) and can also be used to put an upper limit on the stellar and planet radius even considering slightly evolved stars. Third, the presence of an additional fully blended star that contaminates an eclipsing system to mimic a planet transit can be largely ruled out from the transit light curve given a spectral type for the central star. Fourth, the period can be estimated from a single-transit light curve and a measured spectral type. All of these applications can be used to select the best planet transit candidates for mass determination by radial velocity follow-up. To use these applications in practice, the photometric precision and time sampling of the light curve must be high (better than 0.005 mag precision and 5 minute time sampling).
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متن کاملar X iv : a st ro - p h / 02 08 04 2 v 2 3 A ug 2 00 2 Using All - Sky Surveys to Find Planetary Transits
Transits of bright stars offer a unique opportunity to study detailed properties of extrasolar planets that cannot be determined through radial-velocity observations. We propose all-sky small-aperture transit surveys as the best way to find such systems. We derive a general formula for the number of stars that can be probed for such systems as a function of the characteristics of the star, the ...
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