2015/03/26 by Nathan W. C. Leigh, Aaron M. Geller
Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Classical mechanics #Formalism (music) #Globular cluster #Physics #Stars #Statistical physics #Stellar dynamics #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stv685
10 pages, 4 figures, 3 tables; accepted for publication in MNRAS
arxiv created 2015/03/26 · openalex publication_date 2015/04/28 · arxiv updated 2015/06/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We develop a formalism for calculating probabilities for the outcomes of stellar dynamical interactions, based on results from N-body scattering experiments. We focus here on encounters involving up to six particles and calculate probabilities for direct stellar collisions; however our method is in principle valid for larger particle numbers. Our method relies on the binomial theorem, and is applicable to encounters involving any combination of particle radii. We further demonstrate that our base model is valid to within a few per cent for any combination of particle masses, provided the minimum mass ratio is within a factor of a few from unity. This method is particularly suitable for models of collisional systems involving large numbers of stars, such as globular clusters, old open clusters and galactic nuclei, where small subsets of stars may regularly have very close encounters, and the direct integration of all such encounters is computationally expensive. Variations of our method may also be used to treat other encounter outcomes, such as ejections and exchanges.