Speaker
Description
We investigate the impact of stellar cluster initial conditions on the dynamical evolution of planetary systems. Two configurations are considered; a sub-virial fractal distribution and a virialised Plummer distribution. Both models are initialised with a virial radius of $0.5$pc, $150$ stars and $~145$ planetary systems. Five realisations of each configuration are performed with identical stellar and planetary populations, including a debris disk but omitting gas. Clusters are integrated until $30$ Myr using a novel hybrid multi-scale N-body code that resolves planetary systems in cluster environments self-consistently.
The sub-virial fractal cluster exhibits richer dynamics, with asteroids and planets more frequently acquiring high eccentricities and inclinations, along with a larger fraction of captured and rogue objects. Additionally, this cluster configuration has its extreme trans-Neptunian object and Sednoid analogues occupy regions of phase-space in semi-major axis, eccentricity and inclination that are commonly frequented by captured asteroids. Although the virialised Plummer model can produce such objects, by being less dynamically active, the vast majority of asteroids occupying these regions are native rather than captured. Lastly, neither model efficiently forms an Oort Cloud, indicating that Oort Cloud assembly is strongly suppressed in both dynamically active and quiescent cluster.
These results demonstrate that the bodies on relatively wide orbits (a\sim10^{2} au) retain measurable imprints of their birth cluster morphology. These results imply that observed minor-body populations and interstellar object rates may provide constraints on the Sun’s natal cluster morphology. Given that the Sun is thought to have formed in a more massive cluster ($\gtrsim10^{3}$ stars), ongoing work explores how denser and more massive environments further sculpt debris disk evolution.
| Talk category | NOVA Network 2 |
|---|---|
| PhD relevance | 3rd |
