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The evolution of helium-rich subdwarf-B stars
Astrophysics and Space Science, 2004Helium-rich subdwarf-B (He-sdB) stars are extremely rare hot subluminous stars found in the field of our Galaxy as well as in some globular clusters. The existence of these hot helium stars cannot be explained by canonical stellar evolution theories nor can it be explained by normal sdB evolution.
A. Ahmad, C.S. Jeffery
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A search for variable subdwarf B stars in TESS full frame images – I. Variable objects in the southern ecliptic hemisphere [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 S K Sahoo, A Baran, S Sanjayan
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Pulsations in subdwarf B stars
Journal of Astrophysics and Astronomy, 2005Subdwarf B stars play a significant role in close binary evolution and in the hot star content of old stellar populations, in particular in giant elliptical galaxies. While the question of their origin poses several problems for stellar evolution theory, one of their most fascinating properties is the presence of multi-periodic 2–3 minute oscillations.
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1993
Spectroscopic and photometric data give evidence for a large fraction of binary stars among hot subdwarfs. Since our work aims at determining atmospheric parameters and distances of sdB and sdOB stars, we have to take special care of this aspect. We try to deconvolve the photometric data and derive colours for the subdwarf component of the binary.
A. Theissen +3 more
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Spectroscopic and photometric data give evidence for a large fraction of binary stars among hot subdwarfs. Since our work aims at determining atmospheric parameters and distances of sdB and sdOB stars, we have to take special care of this aspect. We try to deconvolve the photometric data and derive colours for the subdwarf component of the binary.
A. Theissen +3 more
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The pulsations in subdwarf B stars
Astronomische Nachrichten, 2001In this paper, I review our present knowledge of the pulsation phenomenon that affects a fraction of the subdwarf B (sdB) stars. The observed properties of this recently discovered class of pulsating stars are summarized and the current status of the theory explaining the driving of the observed pulsations is discussed.
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Progress on the Front of Pulsating Subdwarf B Stars
Astrophysics and Space Science, 2004We briefly review the recent advances that have been made on the front of pulsating subdwarf B (sdB) stars. The first family of sdB pulsators, the EC 14026 stars, was discovered a few years ago and consists of short-period (∼100−200 s) p-mode variables.
Gilles Fontaine +7 more
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Subdwarf B stars in HW Vir systems
EAS Publications Series, 2003Subdwarf B stars (sdB) dominate the populations of faint blue stars and are found in both the old disk (field sdBs) and halo populations (globular cluster members) of our own Galaxy. The origin of sdB stars remains largely a puzzle, but evidence is accumulating that close binary evolution is fundamental to the problem.
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TESS observations of pulsating subdwarf B stars
2020Transiting Exoplanet Survey Satellite (TESS) observations show CD-28 degrees 1974 to be a gravity(g)-mode-dominated hybrid pulsating subdwarf B (sdBV) star. It shows 13 secure periods that form an l = 1 asymptotic sequence near the typical period spacing.
Reed, Michael D. +9 more
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Diffusion Calculations in the Atmospheres of Subdwarf B Stars
2008¨rpceedo,g pthe the conference on "Hot Subdwarf Stars and Related Objects", held 23-27 July, 2007, Otto-Friedrich-Universität, Bamberg (Germany). Edited by Ulrich Heber, C. Simon Jeffery and Ralf Napiwotzki.
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