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

Baluev, R.; Sokov, E.; Jones, H.; Shaidulin, V.; Sokova, I.; Nielsen, L.; Benni, P.; Schneiter, E.; D'Angelo, C.; Fernandez-Lajus, E.; Di Sisto, R.; BAŞTÜRK, ÖZGÜR; Bretton, M.; Wunsche, A.; Hentunen, V-P; Shadick, S.; Jongen, Y.; Kang, W.; Kim, T.; Pakstiene, E.; Qvam, J.; Knight, C.; 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.; Karimov, R.

doi:10.1093/mnras/stz2620

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

Baluev R., Sokov E. N., Jones H. R. A., Shaidulin V. S., Sokova I. A., Nielsen L. D., ...More

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, vol.490, no.1, pp.1294-1312, 2019 (SCI-Expanded, Scopus)

Publication Type: Article / Article
Volume: 490 Issue: 1
Publication Date: 2019
Doi Number: 10.1093/mnras/stz2620
Journal Name: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
Page Numbers: pp.1294-1312
Keywords: methods: data analysis, methods: statistical, techniques: photometric, techniques: radial velocities, surveys, planetary systems, HIGH-PRECISION PHOTOMETRY, LIMB-DARKENING COEFFICIENTS, STELLAR ATMOSPHERE MODELS, LIGHT-CURVE PROJECT, PLANETARY SYSTEM, RADIAL-VELOCITY, HOT JUPITER, TRANSMISSION SPECTRUM, PHYSICAL-PROPERTIES, IMPROVED PARAMETERS
Open Archive Collection: AVESIS Open Access Collection
Ankara University Affiliated: Yes

Abstract

We homogeneously analyse similar to 3.2 x 10(5) photometric measurements for similar to 1100 transit light curves belonging to 17 exoplanet hosts. The photometric data cover 16 years (2004-2019) and include amateur and professional observations. Old archival light curves 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 non-linear transit timing variation (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 of about -7.5 +/- 2.2 ms(-1) yr(-1), 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 homogeneous TTV sample, including 10 ground-based EXPANSION light curves 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.