Results 21 to 30 of about 74,403 (250)
An Initial Survey of White Dwarfs in the Sloan Digital Sky Survey [PDF]
, 2003 An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky (190 square degrees), observed much like the full survey will be, 269 white dwarfs and 56 hot subdwarfs are identified ...
Alan Uomoto +47 more
core +1 more source
The Astrophysical Journal, 1999 We have secured optical spectra for the eight currently known variable DB, or V777 Her, stars. With the help of a new generation of synthetic spectra, spectroscopic effective temperatures are derived for these objects, as well as for 15 other DB or DBA stars above 20,000 K.
A. Beauchamp +6 more
openaire +1 more source
A Strong Test of Electroweak Theory Using Pulsating DB White Dwarf Stars as Plasmon Neutrino Detectors [PDF]
The Astrophysical Journal, 2004 4 pages emulateapj, 3 figures, accepted for ApJ ...
Winget, D. E. +4 more
openaire +2 more sources
Accretion from debris disks onto white dwarfs : Fingering (thermohaline) instability and derived accretion rates [PDF]
, 2013 Recent observations of a large number of DA and DB white dwarfs show evidence of debris disks, which are the remnants of old planetary systems. The infrared excess detected with \emph{Spitzer} and the lines of heavy elements observed in their atmospheres
Deal, M. +4 more
core +3 more sources
The DB gap and a new class of pulsating white dwarfs
EPJ Web of Conferences, 2013 The recent systematic surveys providing enormously massive datasets of white dwarfs show that there is still a deficit of a factor of 2.5 in the DA/non-DA ratio within the temperature range of 30 000 K < Teff < 45 000 K, which has been regarded as the ...
Shibahashi H.
doaj +1 more source
Two new pulsating DB Stars from the EC survey, EC 04207−4748 and EC 05221−4725 [PDF]
Monthly Notices of the Royal Astronomical Society, 2009 We report the discovery of pulsations in two DB stars found in the Edinburgh–Cape blue object survey. The light curve of EC 04207−4748 appears to be dominated by a strong variation at 2235 μHz (447 s) and its first overtone near 4475 μHz (223 s). Two other peaks appear in the periodograms of all three data sets for this star; near 2370 μHz (∼420 s) and
D. Kilkenny +4 more
openaire +1 more source
The Astrophysical Journal, 2022 Abstract We continue our comprehensive theoretical investigation of the spectral evolution of white dwarfs based on sophisticated simulations of element transport. In this paper, we focus on the transformation of PG 1159 stars into DO/DB white dwarfs due to the gravitational settling of heavy elements and then into DQ white dwarfs ...
A. Bédard, P. Bergeron, P. Brassard
openaire +2 more sources
Revisiting the theoretical DBV (V777 Her) instability strip: the MLT theory of convection [PDF]
, 2008 We reexamine the theoretical instability domain of pulsating DB white dwarfs (DBV or V777 Her variables). We performed an extensive $g$-mode nonadiabatic pulsation analysis of DB evolutionary models considering a wide range of stellar masses, for which ...
A H Córsico +5 more
core +2 more sources
The asteroseismological potential of the pulsating DB white dwarf stars CBS 114 and PG 1456+103 [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 10 pages, 10 embedded figures, 3 embedded tables.
Handler, Gerald +2 more
openaire +3 more sources
Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models [PDF]
, 2012 DBV stars are pulsating white dwarfs with atmospheres rich in He. Asteroseismology of DBV stars can provide valuable clues about the origin, structure and evolution of hydrogen-deficient white dwarfs, and may allow to study neutrino and axion physics ...
A. Bischoff-Kim +49 more
core +2 more sources