Dynamical evolution of a cluster of primordial black holes

TL;DR

This paper models the dynamical evolution of a primordial black hole cluster with diverse masses using the Fokker-Planck equation, highlighting the influence of a central massive black hole on density profile changes.

Contribution

It introduces a detailed Fokker-Planck based model for primordial black hole clusters with a wide mass spectrum, including a central massive black hole, to study their evolution.

Findings

Density profile evolution influenced by a central massive black hole

Mass spectrum from $10^{-4} M_{igodot}$ to $100 M_{igodot}$ considered

Cluster total mass of $10^5 M_{igodot}$ modeled

Abstract

Evolution of a cluster of primordial black holes in the two-body relaxation approximation based on the Fokker-Planck equation is discussed. In our calculation, we consider the self-gravitating cluster with a wide range of black holes masses from $10^{-4} M_{\odot}$ up to $100 M_{\odot}$ and the total mass $10^5 M_{\odot}$. Moreover, we included a massive black hole in the cluster center which determines the evolution rate of the density profile in its vicinity.