Related papers: Black Holes and Galaxy Dynamics
We study the dynamical evolution of supermassive black holes (BHs) in merging galaxies on scales of hundreds of kpc to 10 pc, to identify the physical processes that aid or hinder the orbital decay of BHs. We present hydrodynamical…
As star-forming galaxies approach or exceed a stellar mass around $10^{11} M_\odot$, they are increasingly likely to be quenched in a process generically called mass quenching. Central galaxies, which are quenched via mass rather than…
The supermassive black holes originally in the nuclei of two merging galaxies will form a binary in the remnant core. The early evolution of the massive binary is driven by dynamical friction before the binary becomes "hard" and eventually…
This paper constructs an analytic form for a triaxial potential that describes the dynamics of a wide variety of astrophysical systems, including the inner portions of dark matter halos, the central regions of galactic bulges, and young…
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…
The centers of most galaxies contain massive black holes surrounded by dense star clusters. The structure of these clusters determines the rate and properties of observable transient events, such as flares from tidally disrupted stars and…
Using axisymmetric simulations coupling special relativistic MHD, an approximate post-Newtonian gravitational potential and two-moment neutrino transport, we show different paths for the formation of either protomagnetars or stellar mass…
Mini-black holes made of dark matter that can potentially form in the interior of neutron stars have been always thought to grow by accreting the matter of the core of the star via a spherical Bondi accretion. However, neutron stars have…
This paper summarises an investigation of chaos in a toy potential which mimics much of the behaviour observed for the more realistic triaxial generalisations of the Dehnen potentials, which have been used to model cuspy triaxial galaxies…
We investigated the dynamical reaction of the central region of galaxies to a falling massive black hole by N-body simulations. As the initial galaxy model, we used an isothermal King model and placed a massive black hole at around the…
We explore the possibility that massive black holes comprise a significant fraction of the dark matter of our galaxy by studying the dissolution of galactic globular clusters bombarded by them. In our simulations, we evolve the clusters…
We have examined the effect of slow growth of a central black hole on spherical galaxies that obey S\'ersic or $R^{1/m}$ surface-brightness profiles. During such growth the actions of each stellar orbit are conserved, which allows us to…
We study the collapse of rapidly rotating supermassive stars that may have formed in the early Universe. By self-consistently simulating the dynamics from the onset of collapse using three-dimensional general-relativistic hydrodynamics with…
Aims. In this paper we continue our study of density cusps that may contain central black holes. Methods. We recall our attempts to use distribution functions with a memory of self-similar relaxation, but mostly they apply only in…
Three-body interactions are expected to be common in globular clusters and in galactic cores hosting supermassive black holes. Here we consider an equal-mass binary-black-hole system in the presence of a third black hole. Using numerically…
The centers of stellar spheroids are often marked by the presence of nucleated central regions, called nuclear star clusters (NSCs). The origin of NSCs is still unclear. Here we investigate the possibility that NSCs originate from the…
I present galaxy models resulting from violent relaxation in the presence of a pre-existing black hole. The models are computed by maximizing the entropy of the stellar dynamical system. I show that their properties are very similar to…
Recent high-resolution observations indicate that nuclear spirals are often present in the innermost few hundred parsecs of disc galaxies. My models show that nuclear spirals form naturally as a gas response to non-axisymmetry in the…
Close encounters and physical collisions between stars in young dense clusters can result in new channels for stellar evolution, and may lead to the formation of very massive stars and black holes via runaway merging. We present some…
The center of our Galaxy is known to host a massive compact object, Sgr A$^*$, which is commonly considered as a super-massive black hole of $\sim 4\times 10^6$ M$_\odot$. It is surrounded by a dense and massive nuclear star cluster, with a…