Related papers: The Boundary Layer in compact binaries
We consider the evolution of white dwarfs with compact object companions (specifically black holes with masses up to 10^6 solar masses, neutron stars, and other white dwarfs). We suppose that the orbits are initially quite elliptical and…
The observed radii of M dwarfs in eclipsing binaries exceed predicted radii by ~ 5%. To investigate this anomaly, the structure of low-mass stars irradiated by a close companion is considered. Irradiation modifies the surface boundary…
Binaries occur in many astrophysical systems, from young protostellar binaries in star forming regions to supermassive black hole binaries in galaxy centers. In many cases, a circumbinary disk of gas forms around the binary with an orbit…
The temperature of a circumbinary disc edge should undulate due to variations in illumination as a function of binary orbital phase. We explore circumbinary disc temperature variations as a source of broad-band infrared light curve…
Recurring outbursts associated with matter flowing onto compact stellar remnants (black-holes, neutron stars, white dwarfs) in close binary systems, provide strong test beds for constraining the poorly understood accretion process. The…
White dwarfs are the burnt out cores of Sun-like stars and are the final fate of 97% of all stars in our Galaxy. The internal structure and composition of white dwarfs are hidden by their high gravities, which causes all elements, apart…
Using Spitzer Space Telescope photometric observations of the eclipsing, interacting binary WZ Sge, we have discovered that the accretion disk is far more complex than previously believed. Our 4.5 and 8 micron time series observations…
Circumbinary disks crucially affect the orbital and electromagnetic properties of binary systems across the universe, from stars in our galactic neighborhood to supermassive black hole binaries formed as the result of tumultuous galactic…
We investigate the structure and stability against radial oscillations, pycnonuclear reactions, and inverse $\beta$-decay of hot white dwarfs. We regard that the fluid matter is made up for nucleons and electrons confined in a Wigner-Seitz…
The existence of supermassive black holes lurking in the centers of galaxies and of stellar binary systems containing a black hole with a few solar masses has been established beyond reasonable doubt. The idea that black holes of…
During their formative stages, giant planets are fed by infalling material sourced from the background circumstellar disk. Due to conservation of angular momentum, the incoming gas and dust collects into a circumplanetary disk that…
A number of metal-rich white dwarfs (WDs) are known to host compact, dense particle disks, which are thought to be responsible for metal pollution of these stars. In many such systems the inner radii of disks inferred from their spectra are…
Nearly all known white dwarf planetary systems contain detectable rocky debris in the stellar photosphere. A glaring exception is the young and still evolving white dwarf WD J0914+1914, which instead harbours a giant planet and a disc of…
A substantial fraction of stars can be found in wide binaries with projected separations between $\sim10^2$ and $10^5\,\rm AU$. In the standard lore of binary physics, these would evolve as effectively single stars that remotely orbit one…
Universal to black hole X-ray binaries, the high-frequency soft lag gets longer during the hard-to-intermediate state transition, evolving from ${\lesssim}1~{\rm ms}$ to ${\sim}10~{\rm ms}$. The soft lag production mechanism is thermal disk…
We report the statistical properties of stars, brown dwarfs and multiple systems obtained from the largest hydrodynamical simulation of star cluster formation to date that resolves masses down to the opacity limit for fragmentation (a few…
We consider the long-term collisional and dynamical evolution of solid material orbiting in a narrow annulus near the Roche limit of a white dwarf. With orbital velocities of 300 km/sec, systems of solids with initial eccentricity $e…
Aims: We study single and binary white dwarfs in the inner halo of the Milky Way in order to learn more about the conditions under which the population of halo stars was born, such as the initial mass function (IMF), the star formation…
Disk accretion onto a weakly magnetized central object, e.g. a star, is inevitably accompanied by the formation of a boundary layer near the surface, in which matter slows down from the highly supersonic orbital velocity of the disk to the…
Our understanding of the dynamical processes which control the structure and evolution of the interaction region between an accretion disk and the central star is reviewed. If the central star is unmagnetized, this interaction is in the…