We homogeneously reanalyse 124 transit light curves for the WASP-4 b hot Jupiter. This set involved new observations secured in 2019 and nearly all observations mentioned in the literature, including high-accuracy GEMINI/GMOS transmission spectroscopy of 2011-2014 and TESS observations of 2018. The analysis confirmed a nonlinear TTV trend with P/∣P˙∣∼(17−30) Myr (1-sigma range), implying only half of the initial decay rate estimation. The trend significance is at least 3.4-sigma in the agressively conservative treatment. Possible radial acceleration due to unseen companions is not revealed in Doppler data covering seven years 2007-2014, and radial acceleration of −15 m s−1yr−1 reported in a recent preprint by another team is not confirmed. If present, it is a very nonlinear RV variation. Assuming that the entire TTV is tidal in nature, the tidal quality factor Q⋆′∼(4.5−8.5)⋅104 does not reveal a convincing disagreement with available theory predictions.
@article{arxiv.2004.09109,
title = {WASP-4 transit timing variation from a comprehensive set of 129 transits},
author = {R. V. Baluev and E. N. Sokov and S. Hoyer and C. Huitson and José A. R. S. da Silva and P. Evans and I. A. Sokova and C. R. Knight and V. Sh. Shaidulin},
journal= {arXiv preprint arXiv:2004.09109},
year = {2021}
}
Comments
Accepted to MNRAS Letters. 5 pages, 1 figure. TTV data files and an online-only PDF supplement are in the download archive