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arXiv · 2209.10582

Photometry and transit modelling of exoplanet WASP-140b

Abstract

Eleven transit light curves for the exoplanet WASP-140b were studied with the primary objective to investigate the possibility of transit timing variations (TTVs). Previously unstudied MicroObservatory and Las Cumbres Global Telescope Network photometry were analysed using Markov Chain Monte Carlo techniques, including new observations collected by this study of a transit in December 2021. No evidence was found for TTVs. We used two transit models coupled with Bayesian optimization to explore the physical parameters of the system. The radius for WASP-140b was estimated to be $1.38^{+0.18}_{-0.17}$ Jupiter radii, with the planet orbiting its host star in $2.235987 \pm 0.000008$ days at an inclination of $85.75 \pm 0.75$ degrees. The derived parameters are in formal agreement with those in the exoplanet discovery paper of 2016, and somewhat larger than a recent independent study based on photometry by the TESS space telescope.

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Allen North, Timothy Banks. 2022-09-21. Photometry and transit modelling of exoplanet WASP-140b. https://arxiv.org/abs/2209.10582

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