Masses, Radii, Temperatures, Luminosities and Surface Compositions of White Dwarfs
نویسندگان
چکیده
منابع مشابه
M dwarfs: effective temperatures, radii and metallicities
We empirically determine effective temperatures and bolometric luminosities for a large sample of nearby M dwarfs, for which high accuracy optical and infrared photometry is available. We introduce a new technique which exploits the flux ratio in different bands as a proxy of both effective temperature and metallicity. Our temperature scale for late type dwarfs extends well below 3000K (almost ...
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We present a phase-resolved spectroscopic study of the secondary star in the cat-aclysmic variable U Gem. We use our data to measure the radial velocity semi-amplitude, systemic velocity and rotational velocity of the secondary star. Combining this with literature data allows us to determine masses and radii for both the secondary star and white dwarf which are independent of any assumptions ab...
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Globular star clusters are among the first stellar populations to have formed in the Milky Way, and thus only a small sliver of their initial spectrum of stellar types are still burning hydrogen on the main-sequence today. Almost all of the stars born with more mass than 0.8 M⊙ have evolved to form the white dwarf cooling sequence of these systems, and the distribution and properties of these r...
متن کاملContribution of White Dwarfs to Cluster Masses
I have undertaken a literature search through 1997 July 31 of white dwarfs (WDs) in open and globular clusters. I have tried to make a careful evaluation in each case of the likelihood that the object is a WD and that it is a cluster member. The results are presented for 13 open clusters and 11 globular clusters. Currently there are 36 single WDs and Ðve WDs in binaries known among the open clu...
متن کاملSpectral types and masses of white dwarfs in globular clusters , ,
White dwarfs in globular clusters offer additional possibilities to determine distances and ages of globular clusters, provided their spectral types and masses are known. We therefore started a project to obtain spectra of white dwarfs in the globular clusters NGC 6397 and NGC 6752. All observed white dwarfs show hydrogen-rich spectra and are therefore classified as DA. Analysing the multi-colo...
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ژورنال
عنوان ژورنال: International Astronomical Union Colloquium
سال: 1979
ISSN: 0252-9211
DOI: 10.1017/s0252921100075667