Related papers: The Eccentric Disk Model for Superhumps
(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…
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…
We investigate the growth of tidal instabilities in accretion discs in a binary star potential, using three dimensional numerical simulations. As expected from analytic work, the disc is prone to an eccentric instability provided that it is…
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…
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…
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…
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…
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 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.…
We review the theory and observations related to the ``superhump'' precession of eccentric accretion discs in close binary sytems. We agree with earlier work, although for different reasons, that the discrepancy between observation and…
We include the tidal instability due to the 3:1 resonance in the disc instability model developed by Hameury et al. (1998) and modified by Buat-Menard et al. (2001). We confirm earlier results by Osaki (1989) that the tidal instability can…
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,…
We propose a mechanism for the superhump modulations observed in optical photometry of at least two black hole X-ray transients (SXTs). As in extreme mass-ratio cataclysmic variables (CVs), superhumps are assumed to result from the presence…
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…
Superhump amplitudes observed in dwarf novae during their superoutbursts depend on orbital inclination: the maximum amplitudes in systems with low inclinations are $A_\circ \approx 0.25$ mag., while at higher inclinations they increase from…
It is commonly accepted that the periods of superhumps can be satisfactorily explained within a model involving apsidal motion of the accretion disk provided the frequency of the apsidal motion in addition to the dynamical term includes…
In recent years a handful of systems have been observed to show "negative" (nodal) superhumps, with periods slightly shorter than the orbital period. It has been suggested that these modes are a consequence of the slow retrograde precession…
We show that gas disks around the components of an orbiting binary system (so-called minidisks) may be susceptible to a resonant instability which causes the minidisks to become significantly eccentric. Eccentricity is injected by, and also…
We present the results of four magnetohydrodynamic simulations and one alpha-disk simulation of accretion disks in a compact binary system, neglecting vertical stratification and assuming a locally isothermal equation of state. We…
A new mechanism explaining superoutbursts in binaries of SU UMa type is proposed. In the framework of this mechanism the accretion rate increase leading to the superoutburst is associated with formation of a spiral wave of a new…