Related papers: Stellar Tidal Disruption Events by Direct Collapse…
Using cosmological radiation-hydrodynamical simulations, we study the effect of accreting supermassive black holes (SMBHs) on nearby dark-matter (DM) haloes in the very early universe. We find that an SMBH with a spectral energy…
A supermassive black hole in the nucleus of a galaxy will be revealed when a star passes close enough to be torn apart by tidal forces and a flare of radiation is emitted by the stream of stellar debris that plunges into the black hole.…
Stars can be ripped apart by tidal forces in the vicinity of a massive black hole (MBH), causing luminous flares known as tidal disruption events (TDEs). These events could be contributing to the mass growth of intermediate-mass MBHs, and…
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…
It is believed that stellar black holes (BHs) can be formed in two different ways: Either a massive star collapses directly into a BH without a supernova (SN) explosion, or an explosion occurs in a proto-neutron star, but the energy is too…
In dense star clusters, such as globular and open clusters, dynamical interactions between stars and black holes (BHs) can be extremely frequent, leading to various astrophysical transients. Close encounters between a star and a stellar…
The dynamical processes involving stellar-remnant black holes (BH) in stellar clusters has always drawn attention due to the BHs' potential in a number of astrophysical phenomena, especially the dynamical formation of binary black holes…
Direct-collapse black holes (DCBHs) of mass $\sim 10^4$-$10^5 {M}_\odot$ that form in HI-cooling halos in the early Universe are promising progenitors of the $\gtrsim 10^9 {M}_\odot$ supermassive black holes that fuel observed $z \gtrsim 7$…
Direct-collapse black holes (DCBHs) forming at $z \sim$ 20 are currently the leading candidates for the seeds of the first quasars, over 200 of which have now been found at $z >$ 6. Recent studies suggest that DCBHs could be detected in the…
Observations of distant bright quasars suggest that billion solar mass supermassive black holes (SMBHs) were already in place less than a billion years after the Big Bang. Models in which light black hole seeds form by the collapse of…
Understanding the growth of high redshift massive black holes (MBHs) is a problem of great astrophysical interest. The most luminous quasars at $z>6$ are frequently observed but they represent only the tip of the iceberg as the majority of…
We propose the formation of massive pristine dark-matter (DM) halos with masses of $\sim 10^8~M_\odot$, due to the dynamical effects of frequent mergers in rare regions of the Universe with high baryonic streaming velocity relative to DM.…
We study the early stage of the formation of seed supermassive black holes via direct collapse in dark matter (DM) halos, in the cosmological context. We perform high-resolution zoom-in simulations of such collapse at high-$z$. Using the…
Direct-collapse black holes (DCBHs) are an important component of the massive black hole population of the early universe, and their formation and early mergers will be prominent in the data stream of the Laser Interferometer Space Antenna…
We present results from general relativistic calculations of the tidal disruption of white dwarf stars from near encounters with intermediate mass black holes. We follow the evolution of 0.2 and $0.6 M_\odot$ stars on parabolic trajectories…
We present a numerical investigation of the gravitational collapse of horizon-size density fluctuations to primordial black holes (PBHs) during the radiation-dominated phase of the Early Universe. The collapse dynamics of three different…
The concept of stars being tidally ripped apart and consumed by a massive black hole (MBH) lurking in the center of a galaxy first captivated theorists in the late 1970's. The observational evidence for these rare but illuminating phenomena…
Observations by JWST have confirmed the presence of supermassive black holes (BHs) at redshifts $z\gtrsim10$, lending support to scenarios in which BHs experience rapid growth through intense gas accretion. Here we investigate the growth of…
Stars that orbit too close to a black hole can be ripped apart by strong tides, producing a type of luminous transient event called a ``tidal disruption event" (TDE). Tidal disruption events of stars by supermassive black holes (SMBHs)…
The tidal disruption of a star by a massive black hole (MBH) is thought to produce a transient luminous event. Such tidal disruption events (TDEs) may play an important role in the detection and characterization of MBHs and probe the…