相关论文: Enhanced activity of massive black holes by stella…
We build an evolution model of the central black hole that depends on the processes of gas accretion, the capture of stars, mergers as well as electromagnetic torque. In case of gas accretion in the presence of cooling sources, the flow is…
The centers of galaxies host a supermassive black hole surrounded by a dense stellar cluster. The cluster is expected to develop mass segregation, in which gravitational scatterings among the stars cause heavier objects to sink closer to…
Many astrophysical environments, from star clusters and globular clusters to the disks of Active Galactic Nuclei, are characterized by frequent interactions between stars and the compact objects that they leave behind. Here, using a suite…
Supermassive black holes inhabit galactic nuclei, and their presence influences in crucial ways the evolution of the stellar distribution. The low-density cores observed in bright galaxies are probably a result of black hole infall, while…
A bright flare from a galactic nucleus followed at late times by a $t^{-5/3}$ decay in luminosity is often considered the signature of the complete tidal disruption of a star by a massive black hole. The flare and power-law decay are…
Recent analyses have shown that close encounters between stars and stellar black holes occur frequently in dense star clusters. Depending upon the distance at closest approach, these interactions can lead to dissipating encounters such as…
We discuss the structure of a central stellar cluster whose dynamics is influenced by gravitation of a supermassive black hole and by the dissipative interaction of orbiting stars with an accretion disc. We also take the effect of disc…
The orbital decay and tidal disruption of a star cluster in a galaxy is studied in an analytical manner. Owing to dynamical friction, the star cluster spirals in toward the center of the galaxy. Simultaneously, the galactic tidal field…
In this paper we report results of collisional N-body simulations of the dynamical evolution of equal-mass star clusters containing a massive central black hole. Each cluster is composed of between 5,000 to 180,000 stars together with a…
Dynamics of stellar orbits in dense stellar systems and nuclear star clusters (NSC) with an embedded supermassive black hole (SMBH) is governed a complex interplay of different forces. In particular, star--star gravitational collisions…
Supermassive black holes at the centers of galaxies occasionally disrupt stars or consume stellar-mass black holes (BHs) that wander too close, producing observable electromagnetic or gravitational wave signals. We examine how mass…
We propose a scenario in which massive stars form at the outer edges of an AGN accretion disc. We analyze the dynamics of a disc forming around a supermassive black hole, in which the angular momentum is transported by turbulence induced by…
If a Kerr black hole is connected to a disk rotating around it by a magnetic field, the rotational energy of the Kerr black hole provides an energy source for the radiation of the disk in addition to disk accretion. The black hole exerts a…
Disks of gas accreting onto supermassive black holes are thought to power active galactic nuclei (AGN). Stars may form in gravitationally unstable regions of these disks, or may be captured from nuclear star clusters. Because of the dense…
Stars orbiting supermassive black holes can generate recurring accretion flares in repeating partial tidal disruption events (TDEs). Here we develop an efficient formalism for analyzing the time-dependent response of a star to the removal…
We study the formation of accretion disks resulting from dynamical three dimensional binary coalescence calculations, where a neutron star is tidally disrupted before being swallowed by its black hole companion. By subsequently assuming…
We study the evolution of eccentricity and inclination of massive planets in low-density cavities of protoplanetary discs using three-dimensional (3D) simulations. When the planet's orbit is aligned with the equatorial plane of the disc,…
We investigate misaligned accretion discs formed after tidal disruption events that occur when a star encounters a supermassive black hole. We employ the linear theory of warped accretion discs to find the shape of a disc for which the…
We perform high resolution direct $N$-body simulations to study the effect of an accretion disc on stellar dynamics in an active galactic nucleus (AGN). We show that the interaction of the nuclear stellar cluster (NSC) with the gaseous disc…
The black hole of an active galactic nucleus is encircled by an accretion disk. The surface density of the disk is always too low to affect the tidal disruption of a star, but it can be high enough that a vigorous interaction results when…