Related papers: Dynamic Fisheye Grids for Binary Black Holes Simul…
Accretion discs around black holes can become warped by Lense-Thirring precession if the disc is tilted with respect to the black hole spin vector. When the disc viscosity is sufficiently large that warp propagation is diffusive, the inner…
Supermassive black hole binaries are likely to accrete interstellar gas through a circumbinary disk. Shortly before merger, the inner portions of this circumbinary disk are subject to general relativistic effects. To study this regime, we…
A black hole binary approaching merger undergoes changes in its inspiral rate as energy and angular momentum are lost from the orbits into the horizons. This effect strengthens as the black holes come closer. We use numerical relativity…
Numerical schemes for wave-like systems with small dissipation are often inaccurate and unstable due to truncation errors and numerical roundoff errors. Hence, numerical simulations of wave-like systems lacking proper handling of these…
Recent simulations show that the eccentricity of supermassive binary black hole with intermediate mass ratio could grow toward near unity through gravitational interaction with the stellar background in the merging remnant after two…
We present a new approach to studying the evolution of massive black hole binaries in a stellar environment. By imposing conservation of total energy and angular momentum in scattering experiments, we find the dissipation forces that are…
We analyze in detail the spin precession equations in binary black hole systems, when the tidal torque on a Kerr black hole due to quadrupole-monopole coupling is taken into account. We show that completing the precession equations with…
We investigate the accretion flows onto the supermassive binary black holes (SMBBHs) from the circumbinary disk with the equal mass, eccentric binary on the subparsec scale, using Smoothed Particle Hydrodynamics (SPH) code. We find that the…
Stellar-mass binary black holes (BBHs) embedded in active galactic nucleus (AGN) discs are possible progenitors of black-hole mergers detected in gravitational waves by LIGO/VIRGO. To better understand the hydrodynamical evolution of BBHs…
With the forthcoming VLBI images of Sgr A* and M87, simulations of accretion flows onto black holes acquire a special importance to aid with the interpretation of the observations and to test the predictions of different accretion…
The availability of accurate numerical waveforms is an important requirement for the creation and calibration of reliable waveform models for gravitational wave astrophysics. For black hole-neutron star binaries, very few accurate waveforms…
We discuss the gravitational wave emission and the orbital evolution of a hierarchical triple system composed of an inner binary black hole (BBH) and an outer tertiary. Depending on the kick velocity at the merger, the merged BBH could…
Gravitational waves radiated during binary black hole coalescence is a perfect probe for studying the characteristics of strong gravity. Advanced techniques for creating numerical relativity substitute models for eccentric binary black hole…
We present a numerical method for solving the Poisson equation on a nested grid. The nested grid consists of uniform grids having different grid spacing and is designed to cover the space closer to the center with a finer grid. Thus our…
We report a new finite-difference scheme for two-dimensional magnetohydrodynamics (MHD) simulations, with and without rotation, in unstructured grids with quadrilateral cells. The new scheme is implemented within the code VULCAN/2D, which…
We explore the benefits of adapted gauges to small mass ratio binary black hole evolutions in the moving puncture formulation. We find expressions that approximate the late time behavior of the lapse and shift, $(\alpha_0,\beta_0)$, and use…
We introduce a new template for the detection of gravitational waves from compact binary systems which is based on Chebyshev polynomials of the first kind. As well as having excellent convergence properties, these polynomials are also very…
We present a new choice of initial data for binary black hole simulations that significantly improves the efficiency of high-spin simulations. We use spherical Kerr-Schild coordinates, where the horizon of a rotating black hole is…
Perturber objects interacting with supermassive black hole accretion disks are often invoked to explain observed quasi-periodic behavior in active galactic nuclei (AGN). We present global, 3D general relativistic magnetohydrodynamic (GRMHD)…
We investigate close encounters by stellar mass black holes (BHs) in the gaseous discs of active galactic nuclei (AGN) as a potential formation channel of binary black holes (BBHs). We perform a series of 2D isothermal viscous…