Related papers: Circumbinary disks and cataclysmic variable evolut…
We present a study of the gas-driven orbital evolution of unequal mass black hole binaries with circumbinary gas disks (CBDs), varying Mach number and viscosity (nu). Using two-dimensional grid-based hydrodynamics simulations spanning a…
The orbital evolution of cataclysmic variables in which the companion is illuminated by a fraction of the accretion luminosity consists of irradiation-driven limit cycles on thermal timescales, superimposed on a secular evolution toward…
The stability criteria of rapid mass transfer and common envelope evolution are fundamental in binary star evolution. They determine the mass, mass ratio and orbital distribution of many important systems, such as X-ray binaries, Type Ia…
Recent observations of supernovae (SNe) have indicated that a fraction of massive stars possess dense circumstellar medium (CSM) at the moment of their core collapses. They suggest the presence of additional activities of the SN progenitor…
Many high-state non-magnetic cataclysmic variables (CVs) exhibit blue-shifted absorption or P-Cygni profiles associated with ultraviolet (UV) resonance lines. These features imply the existence of powerful accretion disk winds in CVs. Here,…
We have known for a long time that many of the measured white dwarf (WD) masses in cataclysmic variables (CVs) significantly exceed the mean mass of single WDs. This was thought to be related to observational biases, but recent…
The interaction of a massive binary and a non-self-gravitating circumbinary accretion disc is considered. The shape of the stationary twisted disc produced by the binary is calculated. It is shown that the inner part of the disc must lie in…
According to standard evolutionary theory for cataclysmic variables (CVs), angular momentum loss drives CVs to initially evolve from longer to shorter orbital periods until a minimum period is reached (\approx 80 min). At roughly this…
The recent discoveries of circumbinary planets by $\it Kepler$ raise questions for contemporary planet formation models. Understanding how these planets form requires characterizing their formation environment, the circumbinary…
The evolution of a binary star system by various analytic approximations of mass transfer is discussed, with particular attention payed to the stability of these processes against runaway on the thermal and dynamical timescales of the mass…
The disk instability model attributes the outbursts of dwarf novae to a thermal-viscous instability of their accretion disk, an instability to which nova-like stars are not subject. We aim to test the fundamental prediction of the disk…
Although the theory of cataclysmic variable (CV) evolution is able to explain several observational aspects, strong discrepancies have existed for decades between observations and theoretical predictions of the orbital period distribution,…
In this paper, we study the interaction between the supermassive binary black holes in elliptical orbit and their surrounding disk with a gap. The gap in the disk is a low density region formed due to the tidal effects of the less massive…
If the envelope of a massive star is not entirely removed during common envelope (CE) interaction with an orbiting compact (e.g., black hole [BH] or neutron star [NS]) companion, the residual bound material eventually cools, forming a…
We apply the new generation of theoretical models of low-mass stars to secondaries in CVs, focussing on systems above the period gap. The models confirm that the spectral type should be a good indicator of the donor mass. The orbital…
(Abridged) To gain insight into the dynamical influence of a supermassive black hole binary on a circumbinary accretion disk, we investigate the binary and viscous torque densities throughout such a disk, with emphasis on the final density…
Cataclysmic variable stars (CVs) are close binary systems consisting of a white dwarf (primary) that is accreting matter from a low-mass companion star (secondary). From time to time such systems undergo large-amplitude brightenings. The…
We review recent works on the dynamics of circumbinary accretion, including time variability, angular momentum transfer between the disk and the binary, and the secular evolution of accreting binaries. These dynamics can impact stellar…
I present models of disk evolution around young binary stars. I show that the primary factor in determining circumbinary disk lifetimes is the rate of disk photoevaporation. I also find that photoevaporative clearing leaves a signature on…
The study of cataclysmic variables (CVs), and in particular of the evolution of their accretion discs throughout their different brightness states, has benefited largely from the use of indirect imaging techniques. I report on the latest…