Related papers: Negative superhumps in cataclysmic variables drive…
Current stellar evolution models predict that during the core collapse of massive stars, a considerable amount of the stellar material will fall back onto the compact, collapsed remnants (neutron stars or black holes), usually in the form…
Accretion disks in binary systems can exhibit a tilt instability, arising from the interaction between components of the tidal potential and dissipation. Using a linear analysis, we show that the aspect ratios and outer radii of…
We examine the consequences of radiatively driven warping of accretion disks surrounding pre-main-sequence stars. These disks are stable against warping if the luminosity arises from a steady accretion flow, but are unstable at late times…
Massive primordial halos exposed to moderate UV backgrounds are the potential birthplaces of supermassive black holes. In such a halo, an initially isothermal collapse will occur, leading to high accretion rates of…
Binary black holes embedded within the accretion disks that fuel active galactic nuclei (AGN) are promising progenitors for the source of gravitational wave events detected by LIGO/VIRGO. Several recent studies have shown that when these…
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…
Stellar-mass binary black holes may have circumbinary disks if formed through common-envelope evolution or within gaseous environments. Disks can drive binaries into wider and more eccentric orbits, while gravitational waves harden and…
Geometrically thick disks may form after tidal disruption events, and rapid accretion may lead to short flares followed by long-term, lower-level emission. Using a novel accretion disk code which relies primarily on global conservation laws…
We report optical photometric observations of four superoutbursts of the short-period dwarf nova TV Crv. This object experiences two types of superoutbursts; one with a precursor and the other without. The superhump period and period excess…
We present results from fully general relativistic three-dimensional numerical studies of thick-disk accretion onto a rapidly-rotating (Kerr) black hole with a spin axis that is tilted (not aligned) with the angular momentum vector of the…
In this paper, we report on the first 3D general relativistic radiation magnetohydrodynamic simulations of large supercritical accretion discs that are tilted with respect to the black hole spin axis. We explore a range of black hole spin…
Recent observations of gaps and non-axisymmetric features in the dust distributions of transition disks have been interpreted as evidence of embedded massive protoplanets. However, comparing the predictions of planet-disk interaction models…
Tidal interaction between a gaseous disk and a massive orbiting perturber is known to result in angular momentum exchange between them. Understanding astrophysical manifestations of this coupling such as gap opening by planets in…
Many debris disks seen in scattered light have shapes that imply their dust grains trace highly eccentric, apsidally aligned orbits. Apsidal alignment is surprising, especially for dust. Even when born from an apse-aligned ring of parent…
Recent ideas for the origin and persistence of the warps commonly observed in disc galaxies have focused on cosmic infall. We present N-body simulations of an idealized form of cosmic infall onto a disc galaxy and obtain a warp that closely…
When thin accretion disks around black holes are perturbed, the main restoring force is gravity. If gas pressure, magnetic stresses, and radiation pressure are neglected, the disk remains thin as long as orbits do not intersect.…
Protoplanetary disks can exhibit asymmetric temperature variations due to phenomena such as shadows cast by the inner disk or localized heating by young planets. We investigate the disk features induced by these asymmetric temperature…
Recent advances in time-domain astronomy have led to fresh observational insights into intermediate polars, a subtype of magnetic cataclysmic variables generally accreting via a partial accretion disc. These new discoveries include…
We study the development of finite eccentricity in accretion disks in close binary systems using a two-dimensional grid-based numerical scheme. We perform detailed parameter studies to explore the dependence on viscosity, disk aspect ratio,…
On a disk deformed to a non-axisymmetric form, a set of oscillations can be excited by their resonant interaction through the disk deformation (Kato et al. 2011). This resonant instability process has been proposed to suggest a possible…