Related papers: Magnetically gated accretion in an accreting 'non-…
Accreting white dwarfs are often found in close binary systems with orbital periods ranging from tens of minutes to several hours. In most cases, the accretion process is relatively steady, with significant modulations only occurring on…
Magnetically gated accretion has emerged as a proposed mechanism for producing extremely short, repetitive bursts of accretion onto magnetized white dwarfs in intermediate polars (IPs), but this phenomenon has not been detected previously…
Two new magnetic white dwarf accretion binaries with extremely low mass-transfer rates have been discovered in the course of the Sloan Digital Sky Survey. Measured magnetic fields are 42 MG and 57 MG, and one system orbits with a period of…
White dwarfs (WDs) are the most abundant compact objects, and recent surveys have suggested that over a third of WDs in accreting binaries host a strong (B $\gtrsim$ 1 MG) magnetic field. However, the origin and evolution of WD magnetism…
Accretion-driven spin-up of a magnetized white dwarf in a close binary system is discussed. We address a situation in which the magnetic field of the white dwarf is screening during the accretion phase and re-generating due to the field…
We present a broad-band timing analysis of the accreting white dwarf system MV Lyrae based on data obtained with the Kepler satellite. The observations span 633 days at a cadence of 58.8 seconds and allow us to probe 4 orders of magnitude…
The evolution of the magnetic field of an accreting magnetic white dwarf with an initially dipolar field at the surface has been studied for non-spherical accretion under simplifying assumptions. Accretion on to the polar regions tends to…
Rapid bursts at optical wavelengths have been reported for several accreting white dwarfs, where the optical luminosity can increase by up to a factor 30 in less than an hour fading on timescales of several hours, and where the energy…
We report the discovery of three ultracompact binary white dwarf systems hosting accretion disks, with orbital periods of 7.95, 8.68, and 13.15 minutes. This significantly augments the population of mass-transferring binaries at the…
Magnitude-limited samples have shown that 20-25 per cent of cataclysmic variables contain white dwarfs with magnetic fields of Mega Gauss strength, in stark contrast to the approximately 5 per cent of single white dwarfs with similar…
Magnetic cataclysmic variables are close binary systems containing a strongly magnetized white dwarf that accretes matter coming from an M-dwarf companion. High-energy radiation coming from those objects is emitted from the accretion column…
Discoveries of two new white dwarf plus M star binaries with striking optical cyclotron emission features from the Sloan Digital Sky Survey (SDSS) brings to six the total number of X-ray faint, magnetic accretion binaries that accrete at…
We study accretion induced collapse of magnetized white dwarfs as an origin of millisecond pulsars. We apply magnetized accretion disk models to the pre-collapse accreting magnetic white dwarfs and calculate the white dwarf spin evolution.…
Stellar bow shocks are formed when an outflow interacts with the interstellar medium. In white dwarfs accreting from a binary companion, outflows are associated with either strong winds from the donor star, the accretion disk, or a…
This second paper presents an in-depth analysis of the composition of the planetary material that has been accreted onto seven white dwarfs with circumstellar dust and gas emission discs with abundances reported in Paper I. The white dwarfs…
We discuss the evolution of the magnetic field of an accreting white dwarf. We first show that the timescale for ohmic decay in the liquid interior is 8 to 12 billion years for a dipole field, and 4 to 6 billion years for a quadrupole…
About 25-50% of white dwarfs (WDs) show metal lines in their spectra. Among the widely accepted explanations for this effect is that the these WDs are accreting asteroids that are perhaps flung onto the WDs by a planet via resonance, for…
A number of White Dwarfs (WDs) in cataclysmic binaries have shown brightness variations consistent with non-radial oscillations as observed in isolated WDs. A few objects have been well-characterized with photometric campaigns in the hopes…
SW Sextantis systems are nova-like cataclysmic variables that have unusual spectroscopic properties, which are thought to be caused by an accretion geometry having part of the mass flux trajectory out of the orbital plane. Accretion onto a…
We present new XSHOOTER spectra of NLTT5306, a 0.44 $\pm$ 0.04\msun white dwarf in a short period (101\,min) binary system with a brown dwarf companion that is likely to have previously undergone common envelope evolution. We have confirmed…