TOI-837 b: characterisation, formation and evolutionary history of an infant warm Saturn-mass planet

Abstract

We aim to determine the fundamental properties of the $\sim$35 Myr old star TOI-837 and its close-in Saturn-sized planet, and to investigate the system's formation and evolutionary history. We analysed TESS photometry and HARPS spectroscopic data, measured stellar and planetary parameters, and characterised the stellar activity. We performed population synthesis simulations to track the formation history of TOI-837 $b$, and to reconstruct its possible internal structure. We investigated the planetary atmospheric evolution through photo-evaporation, and quantified the prospects for atmospheric characterisation with JWST. TOI-837 $b$ has radius and mass similar to those of Saturn ($r_b$=9.71${}_{-0.60}^{+0.93}$ \rearth, $m_b$=116${}_{-18}^{+17}$ M${}_{\odot }$, and ${\rho }_b$=0.68${}_{-0.18}^{+0.20}$ gcm${}^{-3}$), on a primordial circular orbit. Population synthesis and early migration simulations suggest that the planet could have originated between 2-4 au, and have either a large and massive core, or a smaller Saturn-like core, depending on the opacity of the protoplanetary gas and on the growth rate of the core. We found that photo-evaporation produced negligible effects even at early ages (3-10 Myr). Transmission spectroscopy with JWST is very promising, and expected to provide constraints on atmospheric metallicity, abundance of H${}_2$O, CO${}_2$, CH${}_4$ molecules, and to probe the presence of refractory elements. TOI-837 offers valuable prospects for follow-up observations, which are needed for a thorough characterisation. JWST will help to better constraining the formation and evolution history of the system, and understand whether TOI-837 $b$ is a Saturn-analogue.

Accepted for publication on A&A on June 12 2024

References in corpus (55)

• The Gaia mission
• Gaia Data Release 3: Summary of the content and survey properties
• The Transiting Exoplanet Survey Satellite
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• Dynamical Outcomes of Planet-Planet Scattering
• Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system
• Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec
• Spectrum radial velocity analyser (SERVAL). High-precision radial velocities and two alternative spectral indicators
• Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core
• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• Modern stellar spectroscopy caveats
• Photochemically-produced SO${}_2$ in the atmosphere of WASP-39b
• A planet within the debris disk around the pre-main-sequence star AU Microscopii
• The updated BaSTI stellar evolution models and isochrones: II. alpha-enhanced calculations
• Tracing the formation history of giant planets in protoplanetary disks with Carbon, Oxygen, Nitrogen and Sulphur
• Atomic data for the Gaia-ESO Survey
• The Gaia-Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age
• Four newborn planets transiting the young solar analog V1298 Tau
• Planet-forming material in a protoplanetary disc: the interplay between chemical evolution and pebble drift
• Stellar chromospheric activity of 1,674 FGK stars from the AMBRE-HARPS sample I. A catalogue of homogeneous chromospheric activity
• On The Origins Of Eccentric Close-in Planets
• New constraints on the planetary system around the young active star AU Mic. Two transiting warm Neptunes near mean-motion resonance
• TESS Hunt for Young and Maturing Exoplanets (THYME) II: A 17 Myr Old Transiting Hot Jupiter in the Sco-Cen Association
• How drifting and evaporating pebbles shape giant planets II: Volatiles and refractories in atmospheres
• Chemical Diversity in Protoplanetary Disks and Its Impact on the Formation History of Giant Planets
• TESS Hunt for Young and Maturing Exoplanets (THYME) VI: an 11 Myr giant planet transiting a very low-mass star in Lower Centaurus Crux
• The origin of the high metallicity of close-in giant exoplanets: Combined effect of the resonant and aerodynamic shepherding
• The Gaia-ESO Survey: Empirical estimates of stellar ages from lithium equivalent widths (EAGLES)
• Rapid contraction of giant planets orbiting the 20 million-years old star V1298 Tau
• A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- I. Search for exoplanets and variable stars in the field of 47 Tuc
• The Pyrat Bay Framework for Exoplanet Atmospheric Modeling: A Population Study of Hubble/WFC3 Transmission Spectra
• Irradiation-driven escape of primordial planetary atmospheres II. Evaporation efficiency of sub-Neptunes through hot Jupiters
• Cluster Difference Imaging Photometric Survey. II. TOI 837: A Young Validated Planet in IC 2602
• A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- II. Search for exoplanets in open clusters of the southern ecliptic hemisphere and their frequency
• Volatile-to-sulfur Ratios Can Recover a Gas Giant's Accretion History
• One year of AU Mic with HARPS: I -- measuring the masses of the two transiting planets
• Irradiation-driven escape of primordial planetary atmospheres I. The ATES photoionization hydrodynamics code
• Constraints on the mass and atmospheric composition and evolution of the low-density young planet DS Tuc A b
• The GAPS Programme with HARPS-N at TNG. XXXVII. A precise density measurement of the young ultra-short period planet TOI-1807 b
• Constraining the entropy of formation from young transiting planets
• The GAPS Programme at TNG XXVII. Reassessment of a young planetary system with HARPS-N: is the hot Jupiter V830 Tau b really there?
• A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- III. Exploring the properties of young associations through their variables, dippers, and candidate exoplanets
• A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- IV. Candidate exoplanets around stars in open clusters: frequency and age-planetary radius distribution
• V1298 Tau with TESS: Updated Ephemerides, Radii, and Period Constraints from a Second Transit of V1298 Tau e
• Validation of TESS exoplanet candidates orbiting solar analogues in the all-sky PLATO input catalogue
• Photo-evaporation of close-in gas giants orbiting around G and M stars
• The obliquity of HIP 67522 b: a 17 Myr old transiting hot Jupiter-sized planet
• Radial Velocity Survey for Planets around Young stars (RVSPY) A transiting warm super-Jovian planet around HD 114082, a young star with a debris disk
• The GAPS program at TNG XLVII: The unusual formation history of V1298 Tau
• TOI-837b is a Young Saturn-sized Exoplanet with a Massive 70 $M_{\oplus }$ Core
• Discovering planets with PLATO: Comparison of algorithms for stellar activity filtering
• YOUNG Star detrending for Transiting Exoplanet Recovery (YOUNGSTER) II: Using Self-Organising Maps to explore young star variability in Sectors 1-13 of TESS data

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• The GAPS Programme at TNG. LXV. Precise density measurement of TOI-1430 b, a young planet with an evaporating atmosphere
• The GAPS programme at TNG LXXI. A sub-Neptune suitable for atmospheric characterization in a multiplanet and mutually inclined system orbiting the bright K dwarf TOI-5789 (HIP 99452)