A numerical study of stellar discs in galactic nuclei
Panamarev T. Kocsis B.
1 December 2022Oxford University Press
Monthly Notices of the Royal Astronomical Society
2022#517Issue 46205 - 6224 pp.
We explore the dynamics of stellar discs in the close vicinity of a supermassive black hole (SMBH) by means of direct N-body simulations. We show that an isolated nuclear stellar disc exhibits anisotropic mass segregation meaning that massive stars settle to lower orbital inclinations and more circular orbits than the light stars. However, in systems in which the stellar disc is embedded in a much more massive isotropic stellar cluster, anisotropic mass segregation tends to be suppressed. In both cases, an initially thin stellar disc becomes thicker, especially in the inner parts due to the fluctuating anisotropy in the spherical component. We find that vector resonant relaxation is quenched in the disc by nodal precession, but it is still the most efficient relaxation process around SMBHs of mass 106 M⊙ and above. Two-body relaxation may dominate for less massive SMBHs found in dwarf galaxies. Stellar discs embedded in massive isotropic stellar clusters ultimately tend to become isotropic on the local two-body relaxation time-scale. Our simulations show that the dynamics of young stars at the centre of the Milky Way is mostly driven by vector resonant relaxation leading to an anticorrelation between the scatter of orbital inclinations and distance from the SMBH. If the S-stars formed in a disc less than 10 Myr ago, they may coexist with a cusp of stellar mass black holes or an intermediate mass black hole with mass up to 1000 M⊙ to reproduce the observed scatter of angular momenta.
galaxies: nuclei , Galaxy: centre , methods: numerical , stars: kinematics and dynamics
Text of the article Перейти на текст статьи
Rudolf Peierls Centre for Theoretical Physics, Parks Road, Oxford, OX1 3PU, United Kingdom
Fesenkov Astrophysical Institute, Observatory 23, Almaty, 050020, Kazakhstan
Energetic Cosmos Laboratory, Nazarbayev University, 53 Kabanbay Batyr ave, Astana, 010000, Kazakhstan
Rudolf Peierls Centre for Theoretical Physics
Fesenkov Astrophysical Institute
Energetic Cosmos Laboratory
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026