Gemini spectra of 12 000 K white dwarf stars
نویسندگان
چکیده
منابع مشابه
Improved synthetic spectra of helium-core white dwarf stars
We examine the emergent fluxes from helium-core white dwarfs following their evolution from the end of pre-white dwarf stages down to advanced cooling stages. For this purpose, we include a detailed treatment of the physics of the atmosphere, particularly an improved representation of the state of the gas by taking into account non-ideal effects according to the so-called occupation probability...
متن کاملDiffusion of neon in white dwarf stars.
Sedimentation of the neutron rich isotope 22Ne may be an important source of gravitational energy during the cooling of white dwarf stars. This depends on the diffusion constant for 22Ne in strongly coupled plasma mixtures. We calculate self-diffusion constants D(i) from molecular dynamics simulations of carbon, oxygen, and neon mixtures. We find that D(i) in a mixture does not differ greatly f...
متن کاملRotation velocities of white dwarf stars ?
The narrow Hα line cores observed with the Keck high resolution spectrograph of thirteen hydrogen-rich (DA) white dwarfs are analysed using line blanketed Non-LTE model atmospheres. The synthetic line profiles reproduce the observed line cores very well. Hence no evidence for additional line broadening due to rotation or to magnetic fields can be found. Statistical upper limits to the projected...
متن کاملWhite dwarf stars in D dimensions
We determine the mass-radius relation of relativistic white dwarf stars (a self-gravitating degenerate Fermi gas at T = 0) in a D-dimensional universe and study the influence of the dimension of space on the laws of physics when we combine quantum mechanics, special relativity and gravity. We exhibit characteristic dimensions D = 1, D = 2, D = 3, D = 1 2 (3+ √ 17), D = 4, D = 2(1+ √ 2) and show...
متن کاملHydrogen model atmospheres for white dwarf stars
We present a detailed calculation of model atmospheres for DA white dwarfs. Our atmosphere code solves the atmosphere structure in local thermodynamic equilibrium with a standard partial linearization technique, which takes into account the energy transfer by radiation and convection. This code incorporates recent improved and extended data base of collision induced absorption by molecular hydr...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2006
ISSN: 0035-8711,1365-2966
DOI: 10.1111/j.1365-2966.2006.10992.x