Related papers: Black holes and core expansion in massive star clu…
Utilizing a series of N-body simulations, we argue that gravitationally bound stellar clusters of modest population evolve very differently from the picture presented by classical dynamical relaxation theory. The system's most massive stars…
All gravitationally bound clusters expand, due to both gas loss from their most massive members and binary heating. All are eventually disrupted tidally, either by passing molecular clouds or the gravitational potential of their host…
Massive star clusters are often used as tracers of galaxy formation and assembly. In order to do so, we must understand their properties at formation, and how those properties change with time, galactic environment, and galaxy assembly…
We simulate a cluster of 144179 stars including 13107 primordial hard binaries (10% of the total number of single stars and binary centers of mass), using direct integration of the equations of motion of all stars and binaries and…
Understanding binary black hole (BBH) dynamics in dense star clusters is key to interpreting the gravitational wave detections by LIGO and Virgo. Here, we perform $N$-body simulations of star clusters, focusing on BBH formation mechanisms,…
Dense star clusters expand until their sizes are limited by the tidal field of their host galaxy. During this expansion phase the member stars evolve and lose mass. We show that for clusters with short initial relaxation time scales (<~100…
Star clusters - open and globulars - experience dynamical evolution on time scales shorter than their age. Consequently, open and globular clusters provide us with unique dynamical laboratories for learning about two-body relaxation, mass…
While tens or hundreds of stellar-remnant black holes are expected to form in globular star clusters, it is still unclear how many of those will be retained upon formation, and how many will be ejected through subsequent dynamical…
The study of how stars distribute themselves around a massive black hole (MBH) in the center of a galaxy is an important prerequisite for the understanding of many galactic-center processes. These include the observed overabundance of point…
In a star cluster with a sufficiently large escape velocity, black holes (BHs) that are produced by BH mergers can be retained, dynamically form new BH binaries, and merge again. This process can repeat several times and lead to significant…
In this thesis we study several aspects of dynamical evolution of stellar clusters. The results of more than 200 simulations of single-mass star clusters with different initial total mass, half-mass radius and galactocentric distance, are…
We supplement current evolutionary computations concerning Magellanic Cloud stars by exploring the evolutionary behavior of canonical stellar models (i.e.,with inefficient core overshooting) with metallicities suitable for stars in the…
We investigate the dynamics of stellar-mass black holes (BH) in star clusters focusing on the dynamical formation of BH-BH binaries, which are very important sources of gravitational waves (GW). We examine the properties of these BH-BH…
Stars mostly form in groups consisting of a few dozen to several ten thousand members. For 30 years, theoretical models provide a basic concept of how such star clusters form and develop: they originate from the gas and dust of collapsing…
Star clusters with multi-mass components dynamically evolve faster than those modeled with equal-mass components. Using a series of direct $N$-body simulations, we investigate the dynamical evolution of star clusters with mass functions,…
We propose a scenario for mass evolution of massive black holes (MBH) in galactic nuclei, to explain both the mass correlation of the supermassive black hole (SMBH) with the bulge and the down-sizing behavior of the active galactic nuclei.…
As self-gravitating systems, dense star clusters exhibit a natural diffusion of energy from their innermost to outermost regions, which leads to a slow and steady contraction of the core until it ultimately collapses under gravity. However,…
Dense star clusters are spectacular self-gravitating stellar systems in our Galaxy and across the Universe - in many respects. They populate disks and spheroids of galaxies as well as almost every galactic center. In massive elliptical…
The distribution of core radii of rich clusters in the Large Magellanic Cloud (LMC) systematically increases in both upper limit and spread with increasing cluster age. Cluster-to-cluster variations in the stellar initial mass function…
We report on the results of a direct N-body simulation of a star cluster that started with N = 200 000, comprising 195 000 single stars and 5 000 primordial binaries. The code used for the simulation includes stellar evolution, binary…