Homogeneously derived transit timings for 17 exoplanets and reassessed TTV trends for WASP-12 and WASP-4

Baluev, R V; Sokov, E N; Jones, H R A; Shaidulin, V Sh; Sokova, I A; Nielsen, L D; Benni, P; Schneiter, E M; D’Angelo, C Villarreal; Fernández-Lajús, E; Di Sisto, R P; Baştürk, Ö; Bretton, M; Wunsche, A; Hentunen, V-P; Shadick, S; Jongen, Y; Kang, W; Kim, T; Pakštienė, E; Qvam, J K T; Knight, C R; Guerra, P; Marchini, A; Salvaggio, F; Papini, R; Evans, P; Salisbury, M.; Garcia, F; Molina, D; Garlitz, J; Esseiva, N; Ogmen, Y; Karavaev, Yu; Rusov, S; Ibrahimov, M A and Karimov, R G (2019). Homogeneously derived transit timings for 17 exoplanets and reassessed TTV trends for WASP-12 and WASP-4. Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/stz2620

Abstract

We homogeneously analyse ∼3.2 × 10⁵ photometric measurements for ∼1100 transit lightcurves belonging to 17 exoplanet hosts. The photometric data cover 16 years 2004–2019 and include amateur and professional observations. Old archival lightcurves were reprocessed using up-to-date exoplanetary parameters and empirically debiased limb-darkening models. We also derive self-consistent transit and radial-velocity fits for 13 targets. We confirm the nonlinear TTV trend in the WASP-12 data at a high significance, and with a consistent magnitude. However, Doppler data reveal hints of a radial acceleration about ( − 7.5 ± 2.2) m/s/yr, indicating the presence of unseen distant companions, and suggesting that roughly 10 per cent of the observed TTV was induced via the light-travel (or Roemer) effect. For WASP-4, a similar TTV trend suspected after the recent TESS observations appears controversial and model-dependent. It is not supported by our homogeneus TTV sample, including 10 ground-based EXPANSION lightcurves obtained in 2018 simultaneously with TESS. Even if the TTV trend itself does exist in WASP-4, its magnitude and tidal nature are uncertain. Doppler data cannot entirely rule out the Roemer effect induced by possible distant companions.

Viewing alternatives

Metrics

Item Actions

Export

You can export this page using these formats Digital Object Identifier - DOI