Related papers: Repeating Nuclear Transients from Repeating Partia…
After the destruction of the star during a tidal disruption event (TDE), the cataclysmic encounter between a star and the supermassive black hole (SMBH) of a galaxy, approximately half of the original stellar debris falls back onto the hole…
A popular class of models for interpreting quasi-periodic X-ray eruptions from galactic nuclei (QPEs) invoke collisions between an object on an extreme mass ratio inspiral (EMRI) and an accretion disk around a supermassive black hole. There…
As active galactic nuclei (AGN) `turn on', some stars end up embedded in accretion disks around supermassive black holes (SMBHs) on retrograde orbits. Such stars experience strong headwinds, aerodynamic drag, ablation and orbital evolution…
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…
The tidal breakup of binary star systems by the supermassive black hole (SMBH) in the center of the galaxy has been suggested as the source of both the observed sample of hypervelocity stars (HVSs) in the halo of the Galaxy and the S-stars…
Tidal disruption events (TDEs) of giant stars by supermassive black holes (SMBH) differ significantly from those of main sequence ones. Most (all for SMBH of more than a~ few times 10^5 m_\odot) giant-TDEs are partial: only a fraction of…
Observations of tidal disruption events (TDEs) on a timescale of years after the main flare show evidence of continued activity in the form of optical/UV emission, quasi-periodic eruptions, and delayed radio flares. Motivated by this, we…
Models for tidal disruption events (TDEs) in which a supermassive black hole disrupts a star commonly assume that the highly eccentric streams of bound stellar debris promptly form a circular accretion disk at the pericenter scale. However,…
When a star is tidally disrupted by a supermassive black hole (BH), roughly half of its mass falls back to the BH at super-Eddington rates. Being tenuously gravitationally bound and unable to cool radiatively, only a small fraction f_in <<…
We have carried out general relativistic particle simulations of stars tidally disrupted by massive black holes. When a star is disrupted in a bound orbit with moderate eccentricity instead of a parabolic orbit, the temporal behavior of the…
The disruption of stars by supermassive black holes has been linked to more than a dozen flares in the cores of galaxies out to redshift $z \sim 0.4$. Modeling these flares properly requires a prediction of the rate of mass return to the…
It is of a general interest to look for signatures of stellar bodies orbiting supermassive black holes (SMBHs) in galactic nuclei other than the Galactic center. Previously stellar transits were analyzed in UV, optical, and X-ray domains as…
We present the results from a dense multi-wavelength (optical/UV, near-infrared (IR), and X-ray) follow-up campaign of the nuclear transient AT2017gge, covering a total of 1698 days from the transient's discovery. The bolometric lightcurve,…
Nuclear star clusters (NSCs) and supermassive black holes (SMBHs) both inhabit galactic nuclei, coexisting in a range of bulge masses, but excluding each other in the largest or smallest galaxies. We propose that the transformation of NSCs…
The tidal disruption of a star by a supermassive black hole, and the subsequent accretion of the disrupted debris by that black hole, offers a direct means to study the inner regions of otherwise-quiescent galaxies. These tidal disruption…
We have evidence of X-ray flares in several galaxies consistent with a a star being tidally disrupted by a supermassive black hole (MBH). If the star starts on a nearly parabolic orbit relative to the MBH, one can derive that the fallback…
Following a tidal disruption event (TDE), the accretion rate can evolve from quiescent to near-Eddington levels and back over months - years timescales. This provides a unique opportunity to study the formation and evolution of the…
Detections of the tidal disruption flares (TDFs) of stars by supermassive black holes (SMBHs) are rapidly accumulating as optical surveys improve. These detections may provide constraints on SMBH demographics, stellar dynamics, and stellar…
Tidal Disruption Events (TDEs) are processes where stars are torn apart by the strong gravitational force near to a massive or supermassive black hole. If a jet is launched in such a process, particle acceleration may take place in internal…
When a star passes within the tidal radius of a supermassive black hole, it will be torn apart. For a star with the mass of the Sun ($M_\odot$) and a non-spinning black hole with a mass $<10^8 M_\odot$, the tidal radius lies outside the…