Dissemin is shutting down on January 1st, 2025

Published in

Oxford University Press (OUP), Monthly Notices of the Royal Astronomical Society, 2019

DOI: 10.1093/mnras/stz3034

Links

Tools

Export citation

Search in Google Scholar

Discarding orbital decay in WASP-19b after one decade of transit observations

This paper was not found in any repository, but could be made available legally by the author.
This paper was not found in any repository, but could be made available legally by the author.

Full text: Unavailable

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Green circle
Published version: archiving allowed
Data provided by SHERPA/RoMEO

Abstract

Abstract We present a empirical study of orbital decay for the exoplanet WASP-19b, based on mid-time measurements of 74 complete transits (12 newly obtained by our team and 62 from the literature), covering a 10-year baseline. A linear ephemeris best represents the mid-transit times as a function of epoch. Thus, we detect no evidence of the shortening of WASP-19b’s orbital period and establish an upper limit of its steady changing rate, $\dot{P}=-2.294$ ms yr−1, and a lower limit for the modified tidal quality factor $Q^{\prime }_{⋆ } = (1.23 ± 0.231) \times 10^{6}$. Both are in agreement with previous works. This is the first estimation of $Q^{\prime }_{⋆ }$ directly derived from the mid-times of WASP-19b obtained through homogeneously analyzed transit measurements. Additionally, we do not detect periodic variations in the transit timings within the measured uncertainties in the mid-times of transit. We are therefore able to discard the existence of planetary companions in the system down to a few M⊕ in the first order mean-motion resonances 1:2 and 2:1 with WASP-19b, in the most conservative case of circular orbits. Finally, we measure the empirical $Q^{\prime }_{⋆ }$ values of 15 exoplanet host stars which suggest that stars with Teff ≲ 5600K dissipate tidal energy more efficiently than hotter stars. This tentative trend needs to be confirmed with a larger sample of empirically measured $Q^{\prime }_{⋆ }$.