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arXiv · 1610.09533

Absolute densities, masses, and radii of the WASP-47 system determined dynamically

J. M. Almenara·R. F. Díaz·X. Bonfils·S. Udry
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Abstract

We present a self-consistent modelling of the available light curve and radial velocity data of WASP-47 that takes into account the gravitational interactions between all known bodies in the system. The joint analysis of light curve and radial velocity data in a multi-planetary system allows deriving absolute densities, radii, and masses without the use of theoretical stellar models. For WASP-47 the precision is limited by the reduced dynamical information that is due to the short time span of the K2 light curve. We achieve a precision of around 22% for the radii of the star and the transiting planets, between 40% and 60% for their masses, and between 1.5% and 38% for their densities. All values agree with previously reported measurements. When theoretical stellar models are included, the system parameters are determined with a precision that exceeds that achieved by previous studies, thanks to the self-consistent modelling of light curve and radial velocity data.

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J. M. Almenara, R. F. Díaz, X. Bonfils, S. Udry. 2016-10-29. Absolute densities, masses, and radii of the WASP-47 system determined dynamically. https://doi.org/10.1051/0004-6361/201629770

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