학술논문
Homogeneously derived transit timings for 17 exoplanets and reassessed TTV trends for WASP-12 and WASP-4
Document Type
Working Paper
Author
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.; Karimov, R. G.
Source
Mon. Not. R. Astron. Soc., 2019, V. 490 (1), P. 1294-1312
Subject
Language
Abstract
We homogeneously analyse $\sim 3.2\times 10^5$ photometric measurements for $\sim 1100$ 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 $(-7.5\pm 2.2)$~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.
Comment: 19 pages, 4 figures, 6 tables; revised manuscript submitted to MNRAS; online-only supplements are in the download archive
Comment: 19 pages, 4 figures, 6 tables; revised manuscript submitted to MNRAS; online-only supplements are in the download archive