Results 41 to 50 of about 6,211 (193)
A Radial Velocity Study of Composite-Spectra Hot Subdwarf Stars with the Hobby-Eberly Telescope
, 2012 Many hot subdwarf stars show composite spectral energy distributions indicative of cool main sequence companions. Binary population synthesis (BPS) models demonstrate such systems can be formed via Roche lobe overflow or common envelope evolution but ...
Berger +27 more
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Impact of helium diffusion and helium-flash-induced carbon production on gravity-mode pulsations in subdwarf B stars [PDF]
, 2009 Realistic stellar models are essential to the forward modelling approach in asteroseismology. For practicality however, certain model assumptions are also required. For example, in the case of subdwarf B stars, one usually starts with zero-age horizontal
Aerts, Conny +3 more
core +4 more sources
Annual Review of Astronomy and Astrophysics, 2009 Hot subdwarf stars (sdBs, sdOs) are core helium-burning stars at the blue end of the horizontal branch or have evolved even beyond that stage. They are found in all Galactic stellar populations and are sufficiently common to account for the UV-upturn of early-type galaxies.
openaire +2 more sources
The Age Of Globular Clusters In Light Of Hipparcos: Resolving the Age Problem? [PDF]
, 1997 We review five independent techniques which are used to set the distance scale to globular clusters, including subdwarf main sequence fitting utilizing the recent Hipparcos parallax catalogue.
Axer M. +21 more
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, 2018 Based on data from the ESA Gaia Data Release 2 (DR2) and several ground-based, multi-band photometry surveys we compiled an all-sky catalogue of $39\,800$ hot subluminous star candidates selected in Gaia DR2 by means of colour, absolute magnitude and ...
Fusillo, N. P. Gentile +3 more
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LS IV — 14°116 : A Time-Resolved Spectroscopic Study
Open Astronomy, 2017 LSIV-14 116 is a very unusual subdwarf B star. It pulsates non-radially with high-order g-modes, these pulsations are unexpected and unexplained, as the effective temperature is 6 000K hotter than the blue edge of the hot subdwarf g-mode instability ...
Martin Pamela, Jeffery C. Simon
doaj +1 more source
Observational asteroseismology of hot subdwarf stars [PDF]
, 2010 Hot subdwarf stars are particularly challenging for asteroseismology due to their rapid pulsation periods, intrinsic faintness and relative rarity both in the field and in clusters.
Østensen, Roy H.
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Finding New Hot Subdwarf Stars in SDSS Images
The Astronomical JournalHot subdwarf stars, located at the end of the blue horizontal branch, have a burning helium core, and are crucial for studying stellar structure. Currently, the number of known hot subdwarf star is relatively small.
Jiangchuan Zhang +8 more
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Open Astronomy, 2017 Several post-common envelope binaries have slightly increasing, decreasing or oscillating orbital periods. One of several possible explanations is light travel-time changes, caused by the binary centre-of-mass being perturbed by the gravitational pull of
Bogensberger David +2 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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