Birth cluster simulations of planetary systems with multiple super-Earths: initial conditions for white dwarf pollution drivers

Abstract

Previous investigations have revealed that eccentric super-Earths represent a class of planets which are particularly effective at transporting minor bodies towards white dwarfs and subsequently polluting their atmospheres with observable chemical signatures. However, the lack of discoveries of these planets beyond a few astronomical units from their host stars prompts a better understanding of their orbital architectures from their nascent birth cluster. Here, we perform stellar cluster simulations of 3-planet and 7-planet systems containing super-Earths on initially circular, coplanar orbits. We adopt the typical stellar masses of main-sequence progenitors of white dwarfs (1.5 M⊙ - 2.5 M⊙) as host stars and include 8,000 main-sequence stars following a Kroupa initial mass function in our clusters. Our results reveal that about 30 per cent of the simulated planets generate eccentricities of at least 0.1 by the time of cluster dissolution, which would aid white dwarf pollution. We provide our output parameters to the community for potential use as initial conditions for subsequent evolution simulations.

On the long-term stability of the Solar System in the presence of weak perturbations from stellar flybys

“…Therefore, the change in secular modes will be dominated by the changes to the semi-major axis of the outermost planet. Additionally, numerical studies involving stellar flybys have shown that changes to the architecture of a planetary system correlates with the number of planets and the initial semi-major axis of the outermost planet (Stock et al 2022). Note that we now have a straightforward scaling relationship that goes from encounter parameters (m , b , v∞) to |∆gj/gj|.…”

Dynamics of young stellar clusters as planet-forming environments

“…A growing number of studies are trying to connect the influence of clustered star-forming environment with the architectures of the resulting planet populations (e.g., [136][137][138][139][140][141][142][143]). Many of these focus on dynamical interactions that sculpt already formed planetary systems.…”

The Influence of Tidal Heating on the Habitability of Planets Orbiting White Dwarfs

“…Dynamical models indicate that post-main-sequence evolution of planetary systems and the subsequent evolution into a white dwarf may trigger orbital instabilities (Debes & Sigurdsson 2002;Veras & Veras 2021). Moreover, the subsequent chaotic evolution may disrupt previously stable planetary systems (Veras & Gansicke 2015;Mustill et al 2018;Zink et al 2020;Stock et al 2022). Side effects of these instabilities such as high-eccentricity scattering and collisions between planets or planetary material and the white dwarf may partially explain the observed pollution (Veras et al 2013;Veras & Fuller 2019).…”