A Highly Eccentric Warm Jupiter Orbiting TIC 237913194

TL;DR

This paper reports the discovery of a highly eccentric warm Jupiter orbiting a G-type star, with detailed measurements of its properties, suggesting a complex dynamical history and providing insights into planetary formation and atmospheric processes.

Contribution

The study presents the first detailed characterization of TIC 237913194b, a warm Jupiter with an extreme eccentricity, highlighting its potential for studying planetary atmospheres and dynamical evolution.

Findings

Mass of TIC 237913194b is approximately 1.94 M_J.

Orbit has a period of 15.17 days with eccentricity ~0.58.

Planet's density is similar to Neptune's, indicating a gaseous composition.

Abstract

The orbital parameters of warm Jupiters serve as a record of their formation history, providing constraints on formation scenarios for giant planets on close and intermediate orbits. Here, we report the discovery of TIC 237913194b, detected in full frame images from Sectors 1 and 2 of TESS, ground-based photometry (CHAT, LCOGT), and FEROS radial velocity time series. We constrain its mass to $M_\mathrm{P} = 1.942_{-0.091}^{+0.091}\,{\rm M_{J}} $, and its radius to $R_\mathrm{P} = 1.117_{-0.047}^{+0.054}\,{\rm R_J}$, implying a bulk density similar to Neptune's. It orbits a G-type star (${\rm M}_{\star} = 1.026_{-0.055}^{+0.057}\,{\rm M}_{\odot}$, $V = 12.1$ mag) with a period of $15.17\,$d on one of the most eccentric orbits of all known warm giants ($e \approx 0.58$). This extreme dynamical state points to a past interaction with an additional, undetected massive companion. A tidal evolution analysis showed a large tidal dissipation timescale, suggesting that the planet is not a progenitor for a hot Jupiter caught during its high-eccentricity migration. TIC 237913194b further represents an attractive opportunity to study the energy deposition and redistribution in the atmosphere of a warm Jupiter with high eccentricity.