Chasing the Tides: Searching for Orbital Decay Signatures in Transit Timing Data and Tidal Models for 20 Hot Jupiters

Abstract

In this work, we present a transit timing variation analysis for 20 hot Jupiter systems, which we interpret with theoretical tidal dissipation models. For the majority of the sample, we conclude that a constant orbital period model represents the timing data best. Only WASP-12 b, TrES-1 b and WASP-121 b exhibit a changing orbital period, according to the most up-to-date results. We updated the orbital decay rate of WASP-12 b to $\dot{P}=-29.4\pm 4.0\mathrm{ms}\mathrm{y}{\mathrm{r}}^{-1}$ and the corresponding stellar tidal quality factor to $Q_{\ast }^{\prime }=1.72\pm 0.18\times 10^5$. For TrES-1 b, the median quadratic model suggests a period decrease at a rate of $-14.9\pm 0.6\mathrm{ms}\mathrm{y}{\mathrm{r}}^{-1}$, but the corresponding $Q_{\ast }^{\prime }=570\pm 60$ does not agree with the theoretical estimates, which suggest $Q_{\ast }^{\prime }\sim 10^6$ due to internal gravity wave dissipation. Lastly, WASP-121 b exhibits orbital growth at a rate of $15.1\pm 0.8\mathrm{ms}\mathrm{y}{\mathrm{r}}^{-1}$, and theoretical results support outward migration due to strong inertial wave dissipation.

30 pages, 8 figures, 5(+9) tables. Accepted for publication in PASP