Related papers: Mass Segregation and Transient Formation in Nuclea…
Centers of galaxies host both a supermassive black hole and a dense stellar cluster. Such an environment should lead to stellar collisions, possibly at very high velocities so that the total energy involved is of the same order as…
Star clusters can interact and merge in galactic discs, halos, or centers. We present direct N-body simulations of binary mergers of star clusters with $M_{\star} = 2.7 \times 10^4 \: \mathrm{M_{\odot}}$ each, using the N-body code BIFROST…
We use direct $N$-body calculations to investigate the impact of primordial mass segregation on the size scale and mass-loss rate of star clusters in a galactic tidal field. We run a set of simulations of clusters with varying degrees of…
We study the dynamics of stellar-mass black holes (BH) in star clusters with particular attention to the formation of BH-BH binaries, which are interesting as sources of gravitational waves (GW). We examine the properties of these BH-BH…
Observations have shown that the majority of massive stars, progenitors of black holes (BHs), have on average more than one stellar companion. In triple systems, wide inner binaries can be driven to a merger by the third body due to…
Galactic center black holes appear to be nearly universally surrounded by dense stellar clusters. When these black holes go through an active accretion phase, the multiple components of the accretion disk, stellar cluster, and black hole…
Tidal disruption events occur rarely in any individual galaxy. Over the last decade, however, time-domain surveys have begun to accumulate statistical samples of these flares. What dynamical processes are responsible for feeding stars to…
(Abridged) Interacting galaxies are well-known for their high star formation rates and rich star cluster populations, but the rapidly changing tidal field can also efficiently destroy clusters. We use numerical simulations of merging disc…
Stars wandering too close to supermassive black holes (SMBHs) can be ripped apart by the tidal forces of the black hole. Recent optical surveys have revealed that E+A galaxies are overrepresented by a factor $\sim $ 30, while green galaxies…
A star is tidally disrupted by a supermassive black hole when their separation is shorter than the "tidal radius". This quantity is often estimated on an order-of-magnitude basis without reference to the star's internal structure. Using…
The dynamical assembly of binary black holes (BBHs) in dense star clusters (SCs) is one of the most promising pathways for producing observable gravitational wave (GW) sources, however several other formation scenarios likely operate as…
There has been suggestive evidence of intermediate-mass black holes (IMBHs; 10^{3-5} M_sun) existing in some globular clusters (GCs) and dwarf galaxies, but IMBHs as a population remain elusive. As a main-sequence star passes too close by…
A large fraction of galactic nuclei is expected to host supermassive black hole binaries (BHB), likely formed during the early phase of galaxies assembly and merging. In this paper, we use a large set of state-of-art numerical models to…
We investigated the evolution of a massive galactic nucleus hosting a super-massive black hole (SMBH) with mass $M_\mathrm{SMBH}=10^8 \mathrm{M}_\odot$ surrounded by a population of 42 heavy star clusters (GCs). Using direct $N$-body…
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…
We analyze stellar tidal disruption events as a possible observational signature of gravitational wave induced recoil of supermassive black holes. As a black hole wanders through its galaxy, it will tidally disrupt bound and unbound stars…
We find that the majority of systems hosting multiple tidal disruptions are likely to contain hard binary SMBH systems, and also show that the rates of these repeated events are high enough to be detected by LSST over its lifetime.…
Most stellar evolution models predict that black holes (BHs) should not exist above approximately $50-70$ M$_\odot$, the lower limit of the pair-instability mass gap. However, recent LIGO/Virgo detections indicate the existence of BHs with…
Tidal disruption events (TDEs) result from stars being gravitationally-scattered into low angular momentum orbits around massive black holes. We show that the short lifetimes of massive Population III stars at high redshifts could…
The recent discovery of high-redshift (z > 6) supermassive black holes (SMBH) favors the formation of massive seed BHs in protogalaxies. One possible scenario is formation of massive stars ~ 1e3-1e4 Msun via runaway stellar collisions in a…