Characterizing Near-Resonance Exoplanets among Multi-Planet Systems

Ing-Guey Jiang^1*, Li-Chin Yeh², Rosemary Mardling³, Jose Almenara⁴, Judith Korth⁴, Adrien Leleu⁴

¹Institute of Astronomy, National Tsing Hua University, Hsin-Chu City, Taiwan
²Institute of Computational and Modeling Science, National Tsing Hua University, Hsin-Chu City, Taiwan
³School of Mathematical Science, Monash University, Victoria, Australia
⁴Observatoire de Geneve, University of Geneva, Geneva, Switzerland

* Presenter:Ing-Guey Jiang, email:jiang@phys.nthu.edu.tw

It is not well understood why many exoplanets are near but not trapped in resonances with their neighbors. To figure out a comprehensive picture, it is important to characterize more near-resonance exoplanets in multi-planet systems.

In order to improve the mass measurement and parameter determination of two sub-Neptunes, K2-266 d and K2-266 e, we present new transit observations obtained with CHaracterising ExOPlanets Satellite (CHEOPS) and Transiting Exoplanet Survey Satellite (TESS), increasing the baseline of transit data from a few epochs to 165 epochs for K2-266 d, and to 121 epochs for K2-266 e. With one order of magnitude better precision, we confirm the planets to belong to the population of planets that has been determined to be volatile-rich.

Moreover, the results of several other interesting systems investigated through the transit timing analysis will be summarized.

Keywords: exoplanet, planet formation, resonance