Related papers: Tilted accretion discs in cataclysmic variables: t…
We consider discs that orbit a central object and are tidally perturbed by a circular orbit companion. Such discs are sometimes subject to an eccentric instability due to the effects of certain resonances. Eccentric instabilities may be…
An important goal of the disk instability model is to explain the superhump phenomenon. Superhumps are features found in the light curves of binary systems, characterized by a period slightly different from the binary orbital period. In…
Negative superhumps are photometric modulations in cataclysmic variables with periods slightly shorter than the orbital period. They are usually attributed to retrograde nodal precession of a tilted accretion disk, although the origin and…
Negative superhumps are believed to arise in cataclysmic variable systems when the accretion disk is tilted with respect to the orbital plane. Slow retrograde precession of the line-of-nodes results in a signal---the negative…
We have applied an eccentric accretion disc theory in simplified form to the case of an accretion disc in a binary system, where the disc contains the 3:1 Lindblad resonance. This is relevant to the case of superhumps in SU Ursae Majoris…
The origin of tilted disks in cataclysmic variables is explained in terms of a model involving the stream-disk interactions. Tilted, precessing disk causes periodically variable asymmetry in the irradiation of the two hemispheres of the…
We numerically study the tidal instability of accretion discs in close binary systems using a two-dimensional SPH code. We find that the precession rate of tidally unstable, eccentric discs does not only depend upon the binary mass ratio q.…
Since the discovery of superhumps in 1974, these photometric modulations have provided a crucial observational window into disk instabilities in cataclysmic variable stars, particularly the tidal instability associated with the 3:1…
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…
Although during the last decade new observations and new theoretical results have brought better understanding of the physics of accretion onto compact objects, many old and several new questions and problems await answers and solutions. I…
Accretion disks in close binary systems are subject to a tidally driven parametric instability which leads to the growth of internal waves near the outer edges of such disks (Goodman 1993). These waves are important in understanding the…
We numerically study the precessing disk model for superhump in the SU~UMa subclass of cataclysmic variables, using a two dimensional SPH code specifically designed for thin disk problems. Two disk simulations for a binary with mass ratio…
Tidally distorted accretion disks in binary star systems are subject to a local hydrodynamic instability which excites $m=1$ internal waves. This instability is three dimensional and approximately incompressible. We study the global aspects…
Using smoothed particle hydrodynamics, we numerically simulate steady state accretion discs for Cataclysmic Variable Dwarf Novae systems that have a secondary-to-primary mass ratio (0.35 \le q \le 0.55). After these accretion discs have…
We demonstrate that measurable vertical structure can be excited in the accretion disc of a close binary system by a dipolar magnetic field centred on the secondary star. We present the first high resolution hydrodynamic simulations to show…
The study of outer disc radius variations in close binary systems is important for understanding the structure and evolution of accretion discs. These variations are predicted by models of both quasi steady and time-dependent discs, and…
Accretion disks around black hole, neutron star, and white dwarf systems are thought to sometimes tilt, retrogradely precess, and produce hump-shaped modulations in light curves that have a period shorter than the orbital period. Although…
(Abridged) We use 3D SPH calculations with higher resolution, as well as with more realistic viscosity and sound-speed prescriptions than previous work to examine the eccentric instability which underlies the superhump phenomenon in…
Negative superhumps in cataclysmic variable systems result when the accretion disc is tilted with respect to the orbital plane. The line of nodes of the tilted disc precesses slowly in the retrograde direction, resulting in a photometric…
We present the results of non linear, hydrodynamic simulations, in three dimensions, of the tidal perturbation of accretion discs in binary systems where the orbit is circular and not necessarily coplanar with the disc mid-plane. The…