Related papers: White Dwarf Variability
We describe radial velocity observations of a large sample of apparently single white dwarfs (WDs), obtained in a long-term effort to discover close, double-degenerate (DD) pairs which might comprise viable Type Ia Supernova (SN Ia)…
We present 13 years of pulsation timing measurements of the DBV white dwarf EC 2005-5234. Each of the four O-C diagrams mimic the sinusoidal behavior typically attributed to a planet + WD system. However, the amplitude and phase of the O-C…
The variable star AR Sco was recently discovered to pulse in brightness every 1.97 min from ultraviolet wavelengths into the radio regime. The system is composed of a cool, low-mass star in a tight, 3.55 hr orbit with a more massive white…
Understanding stellar evolution and its effect on planetary systems is crucial for correctly interpreting the chemical constraints of exo-planetary material that can be given to us by white dwarfs. This article will describe how asteroids,…
White dwarfs (WDs) are the stellar core remnants of low mass stars. They are typically divided into three main composition groups: Oxygen Neon (ONe), Carbon Oxygen (CO) and Helium (He) WDs. The evolution of binary systems can significantly…
We present an analytic description of tides raised on a star by a small orbiting body. In particular, we highlight the disproportionate effect of eccentricity and thus the scope for using these tides to detect and characterise the orbits of…
After summarizing the characteristics of different types of dwarf galaxies I briefly review our current state of knowledge of dwarf galaxy evolution in the Local Group, for which we now have a fairly detailed although by no means…
Roughly 2% of white dwarfs harbor planetary debris disks detectable via infrared excesses, but only a few percent of these disks show a gaseous component, distinguished by their double-peaked emission at the near-infrared calcium triplet.…
We present the light curve variations of the two active binaries with hot subdwarf component. According to the brightness variations outside of the eclipses, the giant components of the systems are chromospherically active stars. The dark…
Compact Galactic binaries where at least one member is a white dwarf or neutron star constitute the majority of individually detectable sources for future low-frequency space-based gravitational-wave (GW) observatories; they also form an…
Using high-resolution N-body simulations we study the stellar properties of dwarf spheroidal galaxies resulting from the tidally induced morphological transformation of disky dwarfs on a cosmologically motivated eccentric orbit around the…
Apparent variability of the longitudinal magnetic fields in most stars is caused by rotation, which quantitavely changes projection of the magnetic field configuration on the line of sight. This is a purely geometrical effect and is not…
Flickering is a fast variability observed in all accreting systems. It has been shown that in most cataclysmic variables flickering originates in the accretion disc. However, in polars the strong magnetic field of the white dwarf prevents…
About 25\% -50\% of white dwarfs (WDs) are found to be polluted by heavy elements. It has been argued that the pollution could be caused by the tidal disruption of an approaching planet around the WD, during which a large number of clumps…
White dwarf WD 1145+017 is orbited by several clouds of dust, possibly emanating from actively disintegrating bodies. These dust clouds reveal themselves through deep, broad, and evolving transits in the star's light curve. Here, we report…
The presence of planets around solar-type stars suggests that many white dwarfs should have relic planetary systems. While planets closer than $\sim$ 5~AU will most likely not survive the post-main sequence lifetime of its parent star, any…
This study investigates the conditions under which gravitational waves (GWs) are emitted during the merger of hot white dwarfs (WDs) in a binary system. Traditionally, these systems consist of two low-mass stars or a more massive WD paired…
As the descendants of stars with masses less than 8 M$_{\odot}$ on the main sequence, white dwarfs provide a unique way to constrain planetary occurrence around intermediate-mass stars (spectral types BAF) that are otherwise difficult to…
Recent observations of white dwarfs in globular clusters indicate that these stars may get a velocity kick during their time as giants. This velocity kick could originate naturally if the mass loss while on the asymptotic giant branch is…
Time-resolved low resolution Hubble Space Telescope ultraviolet spectra together with ground-based optical photometry and spectra are used to constrain the temperatures and pulsation properties of six cataclysmic variables containing…