Accretion onto white dwarfs
Infrared observations of white dwarfs and the implications for the accretion of dusty planetary material
... metal-polluted white dwarfs have been associated with the accretion of dusty planetary ...of white dwarfs and demonstrates that no more than ...polluted white dwarfs, ...
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Infrared observations of white dwarfs and the implications for the accretion of dusty planetary material
... metal-polluted white dwarfs have been associated with the accretion of dusty planetary ...of white dwarfs and demonstrates that no more than ...polluted white dwarfs, ...
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Trace hydrogen in helium atmosphere white dwarfs as a possible signature of water accretion
... of white dwarfs with helium-dominated atmospheres contain exceptionally large masses of hydrogen in their convection zones, with the metal-polluted white dwarf GD 16 being one of the earliest ...
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Trace hydrogen in helium atmosphere white dwarfs as a possible signature of water accretion
... Trace hydrogen in helium atmosphere white dwarfs as a possible signature of water accretion 3 Figure 1. SDSS spectrum of GD 17 and VLT X-shooter spectrum of GD 16 (black). Model spectra using the ...
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Trace hydrogen in helium atmosphere white dwarfs as a possible signature of water accretion
... metal-polluted white dwarfs accrete volatile-depleted material, with very low mass frac- tions of C and seemingly devoid of N (Jura 2006; Farihi et ...water accretion on to white dwarfs ...
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Accretion on to Magnetic White Dwarfs
... of accretion shocks at the white dwarf surface such as the anomalous soft-X-ray excess and its time variability provide strong support for the hypothesis that under certain circumstances the field ...
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Theory of Disk Accretion onto Magnetic Stars
... Disk Accretion onto Magnetic Stars Dong Lai 1 , a 1 Department of Astronomy, Cornell University, Ithaca, NY 14853, USA ...Disk accretion onto magnetic stars occurs in a variety of systems, ...
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White Dwarfs in Cataclysmic Variables: An Update
... accreting white dwarfs in non- magnetic and magnetic cataclysmic variables (CVs) based upon synthetic spectral analyses of far ultraviolet ...on white dwarf surface temperatures, since in the area of ...
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The Genesis of Magnetic Fields in White Dwarfs
... Briggs, Ferrario, Tout & Wickramasinghe, MNRAS (2018), (In publication). Genesis of magnetic fields in isolated white dwarfs 3.1 Abstract A dynamo mechanism driven by di ff erential rotation when stars ...
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The properties of cool DZ white dwarfs
... At a maximum density of 7.9 g cm −3 (a pure Fe/Ni composition with no porosity), we arrive to minimum geometric-mean radii of 39 and 45 km for the planetesimals accreted by SDSS J0741+3146 and SDSS J0823+0546, ...
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Element abundances in cool white dwarfs
... 2 Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA e-mail: [email protected] Received 21 December 2001 / Accepted 31 January 2002 Abstract. We present a small data base of ...
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The New Class of Dusty DAZ White Dwarfs
... maximum accretion rates necessary to explain the observed abundances are essentially independent of T eff ; the short atmospheric residence timescales for the hot WDs are balanced by the deeper convective ...
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Infrared variability of two dusty white dwarfs
... polluted white dwarfs often show excess infrared radiation from circumstellar dust disks, which are modeled as a result of tidal disruption of extrasolar minor ...dusty white dwarfs, SDSS ...
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On the angular momentum evolution of merged white dwarfs
... concentrated onto a small fraction of the mass which orbits at greater and greater radii while the rest is accreted onto the central body’ on an approximately dynamical ...the accretion rate for the ...
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Observations of remnant planetary systems at white dwarfs
... around white dwarfs are active on timescales of years, providing an opportunity to test models of planetesimal scattering and ...the accretion rate onto the white dwarf itself suggests ...
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Cold giant planets evaporated by hot white dwarfs
... young white dwarfs has not been ...the white dwarf left behind by the ...solar white dwarf, resulting in detectable photospheric absorption ...into white dwarfs, observational ...
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Interpretation and diversity of exoplanetary material orbiting white dwarfs
... metal-polluted white dwarfs are observed with medium-resolution optical spectroscopy, where photospheric abundances are determined and interpreted through comparison against solar system ...past ...
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Disk accretion onto a magnetized star
... pressure in the azimuthal direction is small and therefore does not oppose significantly the disk ro- tation. Besides it is clear that the disk must compress the magnetic field within the disk inner edge. These features ...
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Pulsating white dwarfs
... Most white dwarfs do not generate energy from nuclear fusion, but radiate due to residual gravita- tional ...of white dwarfs is therefore often simply described as ...average white ...
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Pulsating white dwarfs
... Each single period is determined by the integral of the pulsation kernel (or work function) over the whole star. It cannot distinguish among different distributions, as demonstrated for example by [79]. If different modes ...
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