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OU Astrophysicist Predicts Detached Eclipsing White Dwarfs to Merge Into an Exotic Star（图）
OU Astrophysicist Predicts Detached Eclipsing White Dwarfs to Merge Exotic Star
2017/9/5
A University of Oklahoma astrophysicist, Mukremin Kilic, and his team have discovered two detached, eclipsing double white dwarf binaries with orbital periods of 40 and 46 minutes, respectively. White...
Two New Tidally Distorted White Dwarfs
Galaxy stellar content Distorted White Dwarfs J174140.49+652638.7
2012/2/23
We identify two new tidally distorted white dwarfs (WDs), SDSS J174140.49+652638.7 and J211921.96-001825.8 (hereafter J1741 and J2119). Both stars are extremely low mass (ELM, < 0.2 Msun) WDs in short...
Nucleosynthesis during the Merger of White Dwarfs and the Origin of R Coronae Borealis Stars
Dwarfs Origin Borealis Stars
2011/10/8
Many hydrogen deficient stars are characterised by surface abundance patterns that are hard to reconcile with conventional stellar evolution. Instead, it has been suggested that they may represent the...
A number of so-called ultra-cool white dwarfs have been detected in different surveys so far. However, based on anecdotal evidence it is believed that most or all of these ultra-cool white dwarfs are ...
The impact of chemical differentiation of white dwarfs on thermonuclear supernovae
chemical differentiation thermonuclear supernovae
2011/1/10
Gravitational settling of 22Ne in cooling white dwarfs can affect the outcome of thermonuclear supernovae. We investigate how the supernova energetics and nucleosynthesis are in turn influenced by thi...
Axions and White Dwarfs
Axions White Dwarfs
2011/1/11
White dwarfs are almost completely degenerate objects that cannot obtain energy from the thermonuclear sources and their evolution is just a gravothermal process of cooling. The simplicity of these ob...
Probing Intermediate Mass Black Holes With Optical Emission Lines from Tidally Disrupted White Dwarfs
Probing Intermediate Mass Black Holes Optical Emission Lines
2011/1/13
We calculate the emission line spectrum produced by the debris released when a white dwarf (WD) is tidally disrupted by an intermediate-mass black hole (IMBH; $M\sim 10^{2}-10^{5}\msun$) and we explor...
Evidence for Terrestrial Planetary System Remnants at White Dwarfs
Terrestrial Planetary System Remnants White Dwarfs
2011/1/13
The last several years have brought about a dynamic shift in the view of exoplanetary systems in the post-main sequence, perhaps epitomized by the evidence for surviving rocky planetary bodies at whit...
Double Detonation of Sub-Chandrasekhar White Dwarfs and Subluminous Type Ia Supernovae
Sub-Chandrasekhar White Dwarfs Subluminous Type Ia Supernovae
2011/1/11
Type Ia supernovae are thought to result from thermonuclear explosions of carbon-oxygen white dwarf stars. This model generally explains the observed properties with certain exceptions, like sub-lumin...
A Supersymmetric model for triggering Supernova Ia in isolated white dwarfs
Supersymmetric model Supernova Ia
2010/11/11
In a two parameter phase transition model we fit the rate and several properties of type I super-novae and address the gap in the supermassive black hole mass distribution. One parameter is a critical...
Catalogs of Hot White Dwarfs in the Milky Way from GALEX's Ultraviolet Sky Surveys. Constraining Stellar Evolution
Astronomical Data Bases catalogues — stars white dwarfs — stars evolution — Galaxy
2010/11/11
We present comprehensive catalogs of hot star candidates in the Milky Way, se-lected from GALEX far-UV (FUV, 1344-1786°A) and near-UV (NUV, 1771-2831°A)imaging. The FUV and NUV photometry allows us to...
Connections Between Tilted Accretion Disks Around White Dwarfs and Substellar Companions
Substellar companions infrared excess debris disks protoplanetary disks exo-zodiacal dust
2010/11/16
Accretion disks in white dwarf systems are believed to be tilted. In a recent publication, the lift force has been suggested to be a source to disk tilt, a source that is likely relevant to all accret...
Asymmetric Line Profiles in Spectra of Gaseous Metal Disks Around Single White Dwarfs
Solar and Stellar Astrophysics (astro-ph.SR)
2011/1/7
Around several single DAZ and DBZ white dwarfs metal-rich disks have been observed, which are mostly believed to originate from disruption of smaller rocky planetesimals. In some cases the material do...
Effect of Radiative Levitation on Calculations of Accretion Rates in White Dwarfs
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/29
Elements heavier than hydrogen or helium that are present in the atmospheres of white dwarfs with effective temperatures lower than 25,000 K, are believed to be the result of accretion. By measuring t...
Understanding the Oldest White Dwarfs: Atmospheres of Cool WDs as Extreme Physics Laboratories
Solar and Stellar Astrophysics (astro-ph.SR) Materials Science (cond-mat.mtrl-sci)
2010/12/27
Reliable modeling of the atmospheres of cool white dwarfs is crucial for understanding the atmospheric evolution of these stars and for accurate white dwarfs cosmochronology. Over the last decade {\it...