Revisiting the secondary eclipses of KELT-1b using TESS observations

TL;DR

This study analyzes TESS data to characterize KELT-1b's transits and secondary eclipses, updating its orbital parameters and searching for TTVs, with results indicating no significant timing variations.

Contribution

It provides a refined measurement of KELT-1b's secondary eclipse depth and transit parameters using Gaussian process modeling and MCMC analysis on TESS data.

Findings

Secondary eclipse depth of 388 ppm measured

No significant transit timing variations detected

Updated transit ephemeris for KELT-1b

Abstract

We present the characterization of the transiting planet KELT-1b % ($R_p \simeq 1.15 R_J, M_p \simeq 27.23 M_J $) using data from the Transiting Exoplanet Survey Satellite (TESS). % during cycle $2$ and sector $17$. Our light curve model includes primary transit and secondary eclipse. Here, we model the systematic noise using Gaussian processes (GPs) and fit it to the data using the Markov Chain Monte Carlo (MCMC) method. Modelling of the TESS light curve returns a planet-to-star radius ratio, $p =$ $0.07652_{-0.00028}^{+0.00029}$ and a relatively large secondary eclipse depth of $388_{-13}^{+12}$ ppm. The transit ephemeris of KELT-1b is updated using the MCMC method. Finally, we complement our work by searching for transit timing variations (TTVs) for KELT-1b. We do not find significant variations from the constant-period models in our transit time data.