Multiplicity Of Stars With Planets In The Solar Neighbourhood
Aims: We intended to quantify the impact of stellar multiplicity on the presence and properties of exoplanets.
Methods: We investigated all exoplanet host stars at less than 100 pc using the latest astrometric data from Gaia DR3 and advanced statistical methodologies. We complemented our search for common proper motion and parallax companions with data from the Washington Double Star catalogue and the literature.
After excluding a number of systems based on radial velocity data, and membership in clusters and open associations, or with resolved ultracool companions, we kept 215 exoplanet host stars in 212 multiple-star systems.
Results: We found 17 new companions in the systems of 15 known exoplanet host stars, measured precise angular and projected physical separations and position angles for 236 pairs of stars, compiled key parameters for 276 planets in multiple systems, and established a comparison sample comprising 687 single stars with exoplanets.
With all of this, we statistically analysed a series of hypothesis regarding planets in multiple stellar systems. Although they are only statistically significant at a 2 sigma level, our analysis pointed to several interesting results on the comparison in the mean number of planets in multiple versus single stellar systems and the tendency of high mass planets to be located in closer orbits in multiple systems.
We confirm that planets in multiple systems tend to have orbits with larger eccentricities than those in single systems. In particular, we found a significant (> 4 sigma) preference for planets to exhibit high orbital eccentricities at small ratios between star-star projected physical separations and star-planet semi-major axes.
Schematic configurations of multiple stellar systems with exoplanets. Orange circles are main-sequence stars, cyan circles are subgiant and giant stars, white circles are white dwarfs, small brown circles are brown dwarfs, and black dots are planets. We display our 212 systems with grey background, except for the two systems with circumbinary planets, namely RR Cae and Kepler16, with green background, and the three systems from Table 4 with planets around both stars, with white background. The systems are sorted by increasing separation from the planet host star to the closest companion star. The abscissa is in logarithmic scale. We also display the Solar System in yellow as a comparison. — astro-ph.SR
J. González-Payo, J. A. Caballero, J. Gorgas, M. Cortés-Contreras, M.-C. Gálvez-Ortiz, C. Cifuentes
Comments: Accepted in A&A. 47 Pages, 14 figures and 9 tables (4 tables online)
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)
Report number: aa50048-24
Cite as: arXiv:2407.20138 [astro-ph.SR] (or arXiv:2407.20138v1 [astro-ph.SR] for this version)
Submission history
From: Javier González-Payo
[v1] Mon, 29 Jul 2024 16:05:58 UTC (2,883 KB)
https://arxiv.org/abs/2407.20138
Astrobiology,
