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Supermassive black holes in the centre of galaxies dominate the gravitational potential of their surrounding stellar clusters. In these dense environments, stars follow nearly Keplerian orbits, which get slowly distorted as a result of the potential fluctuations generated by the stellar cluster itself as a whole. In particular, stars undergo a rapid relaxation of their eccentricities through both resonant and non-resonant processes. An efficient implementation of the resonant diffusion coefficients allows for detailed and systematic explorations of the parameter space describing the properties of the stellar cluster. In conjunction with recent observations of the S-cluster orbiting SgrA*, this framework can be used to jointly constrain the distribution of the unresolved, old, background stellar cluster and the characteristics of a putative dark cluster. Specifically, we show how this can be used to estimate the typical mass and cuspide exponent of intermediate-mass black holes consistent with the relaxed state of the distribution of eccentricities in the observed S-cluster. This should prove useful in constraining super massive black hole formation scenarios.
Direct numerical integrations of the Fokker-Planck equation in energy-angular momentum space are carried out for stars orbiting a supermassive black hole (SBH) at the center of a galaxy. The algorithm, which was described in detail in an earlier pape
Globular clusters contain a finite number of stars. As a result, they inevitably undergo secular evolution (`relaxation) causing their mean distribution function (DF) to evolve on long timescales. On one hand, this long-term evolution may be interpre
We use the Milky Ways nuclear star cluster (NSC) to test the existence of a dark matter soliton core, as predicted in ultra-light dark matter (ULDM) models. Since the soliton core size is proportional to mDM^{-1}, while the core density grows as mDM^
We investigate the rate of orbital orientation dilution of young stellar clusters in the vicinity of supermassive black holes. Within the framework of vector resonant relaxation, we predict the time evolution of the two-point correlation function of
We have measured the amount of kinematic substructure in the Galactic halo using the final data set from the Spaghetti project, a pencil-beam high latitude sky survey. Our sample contains 101 photometrically selected and spectroscopically confirmed g