We present an exhaustive photometric and spectroscopic analysis of TOI-837, a F9/G0 35 Myr young star, hosting a transiting exoplanet, TOI-837b, with an orbital period of 8.32d. Utilising data from TESS and ground-based observations, we determine a planetary radius of 0.82 R_J for TOI-837b. Through detailed HARPS spectroscopic time series analysis, we derive a Doppler semi-amplitude of 35 m/s, corresponding to a planetary mass of 0.39 M_J. The derived planetary properties suggest a substantial core of approximately 70 M_E, constituting about 60% of the planet's total mass. This finding poses a significant challenge to existing theoretical models of core formation. We propose that future atmospheric observations with JWST could provide insights into resolving ambiguities of TOI-837b, offering new perspectives on its composition, formation, and evolution.
@article{arxiv.2404.13750,
title = {TOI-837b is a Young Saturn-sized Exoplanet with a Massive 70 $M_{\oplus}$ Core},
author = {Oscar Barragán and Haochuan Yu and Alix Violet Freckelton and Annabella Meech and Michael Cretignier and Annelies Mortier and Suzanne Aigrain and Baptiste Klein and Niamh K. O'Sullivan and Edward Gillen and Louise Dyregaard Nielsen and Manuel Mallorquín and Norbert Zicher},
journal= {arXiv preprint arXiv:2404.13750},
year = {2024}
}