Related papers: The formation and evolution of very massive stars …
As gravitational wave detections increase the number of observed compact binaries (consisting of neutron stars or blacks), we begin to probe the different conditions producing these binaries. Most studies of compact remnant formation focus…
We launch a fully relativistic study of the formation of supermassive black holes via the collapse of supermassive stars. Here we initiate our investigation by analyzing the secular evolution of supermassive stars up to the onset of…
We study the dynamical evolution of a stellar disk orbiting a massive black hole. We explore the role of two-body relaxation, mass segregation, stellar evolution and binary heating in affecting the disk evolution, and consider the impact of…
Star cluster formation is a major mode of star formation in the extreme conditions of interacting galaxies and violent starbursts. Young clusters are observed to form in a variety of such galaxies, a substantial number resembling the…
Massive stars (M> 10Msun) end their lives with spectacular explosions due to gravitational collapse. The collapse turns the stars into compact objects such as neutron stars and black holes with the ejection of cosmic rays and heavy…
Highly condensed gaseous objects with masses larger than 5x10^4 M_sun are called super-massive stars. In the quasistationary contraction phase, the hydrostatic equilibrium is determined by radiation pressure and gravitation. The global…
A luminous X-ray source is associated with a cluster (MGG-11) of young stars \~200pc from the center of the starburst galaxy M82. The properties of the X-ray source are best explained by a black hole with a mass of at least 350Msun, which…
In spite of significant recent and ongoing research efforts, most of the early evolution and long-term fate of young massive star clusters remain clouded in uncertainties. Here, I discuss our understanding of the initial conditions of star…
We present the first study of the dynamical evolution of an isolated star cluster that combines a significant population of primordial binaries with the presence of a central black hole. We use equal-mass direct N-body simulations, with N…
Context: Field stars are not always single stars, but can often be found in bound double systems. Since binary frequencies in the birth places of stars, young embedded clusters, are sometimes even higher than on average the question arises…
The formation and evolution of low-mass stars within dense halos of dark matter (DM) leads to evolution scenarios quite different from the classical stellar evolution. As a result of our detailed numerical work, we describe these new…
We study the circumstances under which first collisions occur in young and dense star clusters. The initial conditions for our direct $N$-body simulations are chosen such that the clusters experience core collapse within a few million…
Theory holds that a star born with an initial mass between about 8 and 140 times the mass of the Sun will end its life through the catastrophic gravitational collapse of its iron core to a neutron star or black hole. This core collapse…
The progenitors of core-collapse supernovae are stars with an initial mass greater than about 8M(sun). Understanding the evolution of these stars is necessary to comprehend the evolution and differences between supernovae. We have…
Massive OB stars play an important role in the evolution of molecular clouds and star forming regions. The OB stars both photo--ionize molecular gas as well as sweep up and compress interstellar gas through winds, ionization fronts, and…
In this lecture we investigate the formation and evolution of black holes in star clusters. The star clusters under consideration are generally rich, containing more than 10^4 stars, and with a density exceeding 10^4 stars/pc^3. Among these…
Most stars form in dense star clusters deeply embedded in residual gas. These objects must therefore be seen as the fundamental building blocks of galaxies. With this contribution some physical processes that act in the very early and also…
So far, stellar population studies have mainly focused on the evolution of single and binary stars. Recent observations show that triple and higher order multiple star systems are common, especially among massive stars. Introducing…
Stars spend most of their lifetime on the main sequence (MS), where hydrogen burning establishes the internal chemical structure that governs the subsequent evolution. In massive stars, mass loss through winds and binary interactions can…
The observable characteristics and subsequent evolution of young stellar populations is dominated by their massive stars. As our understanding of those massive stars and the factors affecting their evolution improves, so our interpretation…