Work

Semianalytical Fokker–Planck Models for Nuclear Star Clusters

Year: 2025

Type: article

Abstract: We study the dynamics of nuclear star clusters, the dense stellar environments surrounding massive black holes in the centers of galaxies. We consider angular momentum diffusion due to two-body scatterings among stellar objects and energy advection due to gravitational-wave emission upon interaction with the central massive black hole. Such dynamics are described by a 2D Fokker–Planck (FP) equation in energy–angular momentum space. Focusing on the transition between the diffusion-dominated region and the advection-dominated one, we utilize self-similarity to obtain a full solution for the steady-state FP equation. This solution provides the density and flux of the stellar objects in nuclear star clusters. This improves the rate estimates for extreme-mass ratio inspirals, and has interesting implications for a new class of galactic center transients called quasiperiodic eruptions.

Source: The Astrophysical Journal

DOI: 10.3847/1538-4357/ada8a8

Authors: Karamveer Kaur, Barak Rom, Re’em Sari

Institutions: Technion – Israel Institute of Technology, Hebrew University of Jerusalem

Language: English

Topic: Astrophysical Phenomena and Observations

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $4,499

Funders: National Science Foundation, Milner Foundation, Israel Science Foundation