We study the efficiency and dynamics of supermassive black hole binary mergers driven by
angular momentum loss to small-scale gas discs. Such binaries form after major galaxy …

At least several percent of solar-type stars possess giant planets. Surprisingly, most move on
orbits of substantial eccentricity. We investigate the hypothesis that interactions between a …

The destiny of planetary systems through the late evolution of their host stars is very
uncertain. We report a metal-rich gas disk around a moderately hot and young white dwarf …

We show that gas disks around the components of an orbiting binary system (so-called
minidisks) may be susceptible to a resonant instability that causes the minidisks to become …

We study the viscous effects on the interaction between the coplanar Be-star disc and the
neutron star in Be/X-ray binaries, using a three-dimensional, smoothed particle …

The current understanding of mass exchange processes between close binary system
(CBS) components is reviewed, with particular attention on the mass flow structure and …

Debris discs which orbit white dwarfs are signatures of remnant planetary systems. We
present 12 yr of optical spectroscopy of the metal-polluted white dwarf SDSS J1228+ 1040 …

The angular momentum of gas feeding a black hole (BH) may be misaligned with respect to
the BH spin, resulting in a tilted accretion disk. Rotation of the BH drags the surrounding …

Hydrodynamical simulations show that circumbinary disks become eccentric, even when the
binary is circular. Here we demonstrate that, in steady state, the disk's eccentricity behaves …

During the process of planet formation, the planet–disc interactions might excite (or damp)
the orbital eccentricity of the planet. In this paper, we present two long (t∼ 3× 105 orbits) …