TIC65910228b: A single-transit discovery of a massive long-period warm Jupiter with TESS

TL;DR

This paper reports the discovery and detailed characterization of TIC65910228b, a long-period warm Jupiter with a mass of about 4.55 Jupiter masses, orbiting an evolved star every 180 days, highlighting the potential of single-transit detections.

Contribution

It confirms a new long-period warm Jupiter from a single transit in TESS data and provides detailed orbital and physical parameters through follow-up observations.

Findings

Discovered a warm Jupiter with 4.55 M_J and 1.088 R_J

Orbits every 180.52 days with eccentricity 0.25

Expands the sample of long-period transiting giant planets

Abstract

Context. Warm Jupiters are excellent case studies for the investigation of giant planet internal structures and formation theories. However, the sample of long-period transiting giants is still small today for a better understanding of this population. Aims. Starting from a single transit found in the Transiting Exoplanet Survey Satellite (TESS) data, we confirm the planetary nature of the signal and measure its orbital parameters, mass, and radius. We put this system in the context of long-period giant transiting planets and analyzed the viability to sustain atmospheric or dynamical follow-up. Methods. We carried out a spectroscopic follow-up using FEROS and PLATOSpec to obtain precise radial velocities. We added a photometric follow-up with HATPI and Observatoire Moana to obtain a more precise estimate of the orbital period. We derived the orbital and physical parameters through a joint analysis of this data. Results. We report the discovery and characterization of TIC65910228b, a transiting warm Jupiter with a mass of $4.554 \pm 0.255$ $M_J$ and a radius of $1.088 \pm 0.061$ $R_J$, orbiting an evolved F-type star every $\sim 180.52$ days in an eccentric orbit ($e = 0.25 \pm 0.04$). Conclusions. This planet joins a still under-explored population of long-period ($P > 100$) massive ($M_p > 4$ $M_J$) transiting giant planets, being one of the few with a mild eccentricity. This target is a nice example of the potential of single-transit events to populate this region of the parameter space.