On the stellar clustering and architecture of planetary systems

Abstract

Revealing the mechanisms shaping the architecture of planetary systems is crucial for our understanding of their formation and evolution. In this context, it has been recently proposed that stellar clustering might be the key in shaping the orbital architecture of exoplanets. The main goal of this work is to explore the factors that shape the orbits of planets. We used a homogeneous sample of relatively young FGK dwarf stars with RV detected planets and tested the hypothesis that their association to phase space (position-velocity) over-densities ('cluster' stars) and under-densities ('field' stars) impacts the orbital periods of planets. When controlling for the host star properties, on a sample of 52 planets orbiting around 'cluster' stars and 15 planets orbiting around 'field' star, we found no significant difference in the period distribution of planets orbiting these two populations of stars. By considering an extended sample of 73 planets orbiting around 'cluster' stars and 25 planets orbiting 'field' stars, a significant different in the planetary period distributions emerged. However, the hosts associated to stellar under-densities appeared to be significantly older than their 'cluster' counterparts. This did not allow us to conclude whether the planetary architecture is related to age, environment, or both. We further studied a sample of planets orbiting 'cluster' stars to study the mechanism responsible for the shaping of orbits of planets in similar environments. We could not identify a parameter that can unambiguously be responsible for the orbital architecture of massive planets, perhaps, indicating the complexity of the issue. Conclusions. Increased number of planets in clusters and in over-density environments will help to build large and unbiased samples which will then allow to better understand the dominant processes shaping the orbits of planets.

Revised following Referee's comments. A&A

References in corpus (14)

• The NumPy array: a structure for efficient numerical computation
• Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes
• Basic physical parameters of a selected sample of evolved stars
• Planet-planet scattering in planetesimal disks
• On the Occurrence Rate of Hot Jupiters in Different Stellar Environments
• Observational evidence for two distinct giant planet populations
• Heavy metal rules. I. Exoplanet incidence and metallicity
• Connecting substellar and stellar formation. The role of the host star's metallicity
• Investigating the Planet-Metallicity Correlation for Hot Jupiters
• On the survival of resonant and non-resonant planetary systems in star clusters
• Highly inclined and eccentric massive planets. II. Planet-planet interactions during the disc phase
• Bridging the Planet Radius Valley: Stellar Clustering as a Key Driver for Turning Sub-Neptunes into Super-Earths
• Hot Jupiter and ultra-cold Saturn formation in dense star clusters
• Multiple Populations of Extrasolar Gas Giants

Cited by in corpus (17)

• Investigating the architecture and internal structure of the TOI-561 system planets with CHEOPS, HARPS-N and TESS
• Population study on MHD wind-driven disc evolution -- Confronting theory and observation
• Exoplanets in the Galactic context: Planet occurrence rates in the thin disk, thick disk and stellar halo of Kepler stars
• The influence of the environment on the spin evolution of low-mass stars. I. External photoevaporation of circumstellar disks
• Ariel stellar characterisation: I -- homogeneous stellar parameters of 187 FGK planet host stars Description and validation of the method
• The PLATO field selection process. II. Characterization of LOPS2, the first long-pointing field
• A framework for the architecture of exoplanetary systems. II. Nature versus nurture: Emergent formation pathways of architecture classes
• Hot Jupiters, cold kinematics: High phase space densities of host stars reflect an age bias
• Close stellar flybys common in low-mass clusters
• Multi techniques approach to identify and/or constrain radial velocity sub-stellar companions
• Ariel stellar characterisation II. Chemical abundances of carbon, nitrogen, and oxygen for 181 planet-host FGK dwarf stars
• The Impact of Stellar Clustering on the Observed Multiplicity of Super-Earth systems: Outside-in Cascade of Orbital Misalignments Initiated by Stellar Flybys
• Making hot Jupiters in stellar clusters: the importance of binary exchange
• Chemical composition of planetary hosts: C, N, and $\alpha$-element abundances
• Collision of Two Stellar Associations in the Nearby Gum Nebula
• The Great Planetary Heist: Theft and capture in star-forming regions
• Chemical diversity of the atmospheres and interiors of sub-Neptunes: a case study of GJ 436 b