Related papers: Dynamics of galactic nuclei: Mass segregation and …
Dynamical interactions in dense star clusters are considered one of the most effective formation channels of binary black holes (BBHs). Here, we present direct $N-$body simulations of two different star cluster families: low-mass…
Recent observational studies of ultra-compact dwarf galaxies (UCDs) have discovered massive black holes (MBHs) with masses of more than ${10^6~\rm M_\odot}$, in their central regions. We here consider that these MBHs can be formed through…
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…
We study the number and interaction rates of supermassive black holes in galactic bulges as predicted by hierarchical models of galaxy formation in which the spheroidal components of galaxies are formed by mergers. In bright ellipticals,…
In many theoretical scenarios it is expected that intermediate-mass black holes (IMBHs, with masses M ~ 100-10000 solar masses) reside at the centers of some globular clusters. However, observational evidence for their existence is limited.…
We have re-examined the relation between the mass of the central black holes in nearby galaxies, M_bh, and the stellar mass of the surrounding spheroid or bulge, M_bulge. For a total of 30 galaxies bulge masses were derived through Jeans…
Theoretical modeling of massive stars predicts a gap in the black hole (BH) mass function above $\sim 40-50\,M_{\odot}$ for BHs formed through single star evolution, arising from (pulsational) pair-instability supernovae. However, in dense…
Dynamical interactions in dense star clusters could significantly influence the properties of black holes, leaving imprints on their gravitational-wave signatures. While previous studies have mostly focused on repeated black hole mergers…
If the stellar population of the bulge contains black holes formed in the final core collapse of ordinary stars with M \ga 30 M_{\odot}, then about 25,000 stellar mass black holes should have migrated by dynamical friction into the central…
Despite observed strong correlations between central supermassive black holes (SMBHs) and star-formation in galactic nuclei, uncertainties exist in our understanding of their coupling. We present observations of the ratio of…
Supermassive black holes (SMBHs) are a ubiquitous component of the nuclei of galaxies. It is normally assumed that, following the merger of two massive galaxies, a SMBH binary will form, shrink due to stellar or gas dynamical processes and…
Galaxies with stellar bulges are generically observed to host supermassive black holes (SMBHs). The hierarchical merging of galaxies should therefore lead to the formation of SMBH binaries. Merging of old massive galaxies with little gas…
Recent numerical simulations of the fragmentation of primordial molecular clouds in hierarchical cosmogonies have suggested that the very first stars (the so-called Population III) may have been rather massive. Here we point out that a…
The discovery of hundreds of young, bright stars within a parsec from the massive black hole at the center of the Galaxy presents a challenge to star formation theories. The requisite Roche densities for the gravitational collapse of gas…
We study the early dynamical evolution of young, dense star clusters using Monte Carlo simulations for systems with up to N~10^7 stars. Rapid mass segregation of massive main-sequence stars and the development of the Spitzer instability can…
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…
Using results from structural analysis of a sample of nearly 1000 local galaxies from the Sloan Digital Sky Survey, we estimate how the mass in central black holes is distributed amongst elliptical galaxies, classical bulges and…
The coalescence of supermassive black holes (SMBHs) should generate the strongest sources of gravitational waves (GWs) in the Universe. However, the dynamics of their coalescence is the subject of much debate. In this study, we use a suite…
We perform N-body simulations on a multiple massive black hole (MBH) system in a host galaxy to derive the criteria for successive MBH merger. The calculations incorporate the dynamical friction by stars and general relativistic effects as…
We present new upper limits for black hole masses in extremely late type spiral galaxies. We confirm that this class of galaxies has black holes with masses less than 10^6 Msolar, if any. We also derive new upper limits for nuclear star…