Search results
Results from the WOW.Com Content Network
Be–white dwarf X-ray binary systems (BeWDs) are a rare type of X-ray binary consisting of a white dwarf that accretes matter from a rapidly-rotating Be star. These systems form through binary evolution where mass transfer spins up the accretor to become a Be star while the donor evolves into a white dwarf. [2]
The white dwarf PHL 5038A was discovered in 2006 in data from the Sloan Digital Sky Survey [3] and the brown dwarf companion was discovered in 2009 from UKIDSS infrared excess and confirmed with Gemini North to be a spacially resolved binary. [4] It was only the fourth known brown dwarf to orbit a white dwarf at the time. The others were GD ...
As white dwarf stars form at the end of a star's main sequence evolutionary period, such a long-lived star system may have wandered far from the region where it originally formed. Thereafter a close binary system may spend another million years in the mass transfer stage (possibly forming persistent nova outbursts) before the conditions are ...
SDSS 1557 (SDSS J155720.77+091624.6, WD 1554+094) is a binary system composed of a white dwarf and a brown dwarf.The system is surrounded by a circumbinary debris disk.The debris disk was formed when a minor planet was tidally disrupted around the white dwarf in the past.
An intermediate-mass binary pulsar (IMBP) is a pulsar-white dwarf binary system with a relatively long spin period of around 10–200 ms consisting of a white dwarf with a relatively high mass of approximately . [7] The spin periods, magnetic field strengths, and orbital eccentricities of IMBPs are significantly larger than those of low mass binary pulsars (LMBPs). [7]
A symbiotic binary is a type of binary star system, often simply called a symbiotic star. They usually contain a white dwarf with a companion red giant . The cool giant star loses material via Roche lobe overflow or through its stellar wind , which flows onto the hot compact star, usually via an accretion disk .
Although the white dwarf shows evidence of accretion in the past, at present it is not accreting significantly, and the system is powered by the spin-down of the white dwarf. [7] [5] The white dwarf's rotation will slow down on a timescale of 10 7 years. [5] It has a radius of about 7 × 10 3 km, [5] about the same size as Earth.
HM Cancri (also known as HM Cnc or RX J0806.3+1527) is a binary star system about 1,600 light-years (490 pc; 1.5 × 10 16 km) away. [2] It comprises two dense white dwarfs orbiting each other once every 5.4 minutes, at an estimated distance of only 80,000 kilometres (50,000 miles) apart (about 1/5 the distance between the Earth and the Moon).