Measure the spin-up of hot Jupiters due to tides
Creators
- 1. Instituto de Astrofısica e Ciencias do Espaco, Universidade do Porto, CAUP, Porto, Portugal / Departamento de Fısica e Astronomia, Faculdade de Ciencias, Universidade do Porto, Porto, Portugal
Contributors
Editor:
Description
Tidal interaction between a star and a close-in exoplanet leads to shrinkage of the planetary orbit and eventual tidal disruption of the planet. For some of the known exoplanets the expected orbital period variation due to tides is observable over 10 years and they are expected to have measurable tidal decay by now. We analyze TESS data for two targets known to host close-in hot Jupiters: WASP-18 and WASP-4. We aim to measure the current limits on tidal decay which will provide new constrains on the modified tidal quality factor Q′*. We fit the transit parameters for each target using all TESS data available and use the updated parameters to fit the mid-transit times of each individual transit. We use previously published timings with our results to find the change in period with a quadratic ephemerides model and verify the presence of orbital decay. We obtain a new value for Q′* for WASP-4b and we update the minimum Q′* for WASP-18b. We observe a clear period change in WASP-4b and an indication of decreasing period in WASP-18b, but we still do not have enough precision to constrain Q′* significantly on the latter.
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Additional details
References
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