Related papers: PS1-10jh - a tidal disruption event with an extrem…
Tidal disruption events are routinely discovered as bright optical/UV flares, the properties of which are now well categorized on the population level. The underlying physical processes that produce the evolution of their X-ray emission and…
Primordial black holes (PBHs) are dark matter candidates that span broad mass ranges from $10^{-17}$ $M_\odot$ to $\sim 100$ $M_\odot$. We show that the stochastic gravitational wave background can be a powerful window for the detection of…
21-cm radio signal has emerged as an important probe in investigating the dark age of the Universe (recombination to reionization). In the current analysis, we explore the combined effects of primordial black holes (PBH), cooling off of the…
We present simulations of the tidal disruption of a solar mass star by a $10^6M_{\odot}$ black hole. These, for the first time, cover the full time evolution of the tidal disruption event, starting well before the initial encounter and…
A star destroyed by a supermassive black hole (SMBH) in a tidal disruption event (TDE) enables the study of SMBHs. We propose that the distance within which a star is completely destroyed by a SMBH, defined $r_{\rm t, c}$, is accurately…
The flare produced when a star is tidally disrupted by a supermassive black hole holds potential as a diagnostic of both the black hole mass and the star mass. We propose a new method to realize this potential based upon a physical model of…
We study the interaction of a supermassive black hole (SMBH) binary and a standard radiatively efficient thin accretion disk. We examine steady-state configurations of the disk and migrating SMBH system, self-consistently accounting for…
This work explores a scenario for micro-tidal disruption events (TDEs) triggered by close encounters between high-speed white dwarfs (WDs) and stellar-mass black holes (sBHs) in galactic centers. In this model, a WD orbiting the central…
We explore the rates of tidal disruption events (TDEs) of stars by supermassive black holes (SBHs) in galactic nuclei formed in mergers followed by a formation and coalescence of a binary SBH. Such systems initially have a deficit of stars…
We model the intermediate-mass black hole HLX-1, using the Hubble Space Telescope, XMM-Newton and Swift. We quantify the relative contributions of a bluer component, function of X-ray irradiation, and a redder component, constant and likely…
Apparently periodic optical variations of the luminous high-redshift (z=2.06) quasar PSO J334.2028+1.4075 led Liu et al. (2015) to interpret the variability as the orbital period of a binary supermassive black hole (SMBH) residing in a…
We use numerical simulations of circumplanetary disks to determine the boundary between disks that are radially truncated by the tidal potential, and those where gas escapes the Hill sphere. We consider a model problem, in which a coplanar…
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…
The existence of light, fundamental bosonic fields is an attractive possibility that can be tested via black hole observations. We study the effect of a tidal field -- caused by a companion star or black hole -- on the evolution of…
The evolution of the stellar debris after tidal disruption due to the super massive black hole's tidal force is difficult to solve numerically because of the large dynamical range of the problem. We developed an SPH (Smoothed Particle…
We present ground-based and Swift photometric and spectroscopic observations of the tidal disruption event (TDE) ASASSN-15oi, discovered at the center of 2MASX J20390918-3045201 ($d\simeq216$ Mpc) by the All-Sky Automated Survey for…
We present continued radio observations of the tidal disruption event SwiftJ164449.3+573451 extending to \sim216 days after discovery. The data are part of a long-term program to monitor the expansion and energy scale of the relativistic…
Strongly supercooled first-order phase transitions have been proposed as a primordial black hole (PBH) production mechanism. While previous works rely on simplified models with limited thermodynamic precision, we stress that reliable…
We point out that the tidal disruption of a giant may leave a luminous (10^35-10^39 ergs/s), hot (10-100 eV) stellar core. The ``supersoft'' source detected by Chandra at the center of M31 may be such a core; whether or not it is, the…
While once rare, observations of stars being tidally disrupted by supermassive black holes are quickly becoming commonplace. To continue to learn from these events it is necessary to robustly and systematically compare our growing number of…