Results 21 to 30 of about 91 (85)
Orbital periods of 22 subdwarf B stars [PDF]
Monthly Notices of the Royal Astronomical Society, 2003 Subdwarf B (sdB) stars are thought to be core helium burning stars with low mass hydrogen envelopes. In recent years it has become clear that many sdB stars lose their hydrogen through interaction with a binary companion and continue to reside in binary systems today.
L. Morales-Rueda +4 more
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Binary Hypothesis for the Subdwarf B Stars
The Astrophysical Journal, 1976 While observational evidence exists for the composite nature of some of the subdwarf B stars, the conservation of total mass and angular momentum produces a companion whose visual magnitude is similar to that of the subdwarf in the cases we consider.
John G. Mengel +2 more
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Detection of pulsations in three subdwarf B stars [PDF]
Astronomy & Astrophysics, 2001 We report the detection of short period oscillations in the sdB stars HS 0815+4243, HS 2149+0847 and HS 2201+2610 from time-series photometry made at the Nordic Optical Telescope (NOT) from a sample of 31 candidates. Hence these three hot subdwarfs are new members of the EC 14026 class of pulsating sdB stars.
R. Østensen +5 more
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The OB-type subdwarf HD 149382 and the nature of the subdwarf B stars
The Astrophysical Journal, 1975 High-dispersion spectra and monochromatic continuum measures of the subdwarf OB star HD 149382 have been obtained and analyzed to yield the atmospheric parameters T)=40,000 K, log g=5.8. Helium is deficient by a factor 10 compared to Population I. Sulfur is the only element, other than hydrogen and helium, observed in the blue spectrum of this object ...
B. Baschek, J. Norris
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Hot subdwarf stars in close-up view [PDF]
Astronomy & Astrophysics, 2013 Context: Hot subdwarf B stars (sdBs) are considered to be core helium-burning stars with very thin hydrogen envelopes situated on or near the extreme horizontal branch (EHB). The formation of sdBs is still unclear as well as the chemical composition of their atmospheres. The observed helium depletion is attributed to atmospheric diffusion.
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The detection of binary companions to subdwarf B stars [PDF]
Monthly Notices of the Royal Astronomical Society, 1998 Intermediate dispersion spectroscopy of a sample of 40 hot subdwarf B stars between 5500 and 9000A has been obtained. The sample includes a large fraction of targets which have been studied photometrically. Seven targets show strong lines arising from the infrared Ca ii triplet, the unequivocal signature of a cool companion.
C. S. Jeffery, D. L. Pollacco
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On the 3He anomaly in hot subdwarf B stars
Open Astronomy, 2017 AbstractDecades ago,
Schneider, David +4 more
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The Potential of Multicolor Photometry for Pulsating Subdwarf B Stars
The Astrophysical Journal Supplement Series, 2005 Accepted for publication in The Astrophysical Journal Supplement ...
Randall, S. K. +3 more
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Progress in the study of pulsating subdwarf B stars [PDF]
Proceedings of the International Astronomical Union, 2015 AbstractDuring Kepler's main mission, nearly 20 pulsating subdwarf B (sdB: extreme horizontal branch stars) were discovered. Many of these stars were observed for three years, accumulating over 1.5 million observations. Only through these extended observations have we been able to identify pulsation modes, applying constraints for structure models ...
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Asteroseismic Analysis of Pulsating Subdwarf B Stars [PDF]
International Astronomical Union Colloquium, 2002 AbstractWe briefly present a method to perform detailed asteroseismological analyses of pulsating subdwarf B (sdB) stars (also referred to as the EC14026 stars). We use a forward approach based on the computation of large grids of sdB stellar models (each model being analyzed with a linear nonadiabatic pulsation code) to derive, in an objective way ...
S. Charpinet, G. Fontaine, P. Brassard
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