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Asteroseismic Observations of Hot Subdwarfs

open access: yesFrontiers in Astronomy and Space Sciences, 2021
There are a number of reasons for studying hot subdwarf pulsation; the most obvious being that these stars remain a poorly understood late-stage of stellar evolution and knowledge of their interior structure, which pulsation studies reveal, constrains ...
A. E. Lynas-Gray   +2 more
doaj   +2 more sources

Kinematics of nearby Subdwarfs [PDF]

open access: greenAstrophysics and Space Science, 1999
Latex, 4 pages, 6 figures. To appear in the proceedings of the `Galaxy Evolution' conference held in Meudon, September, 21 - 25 ...
Fuchs, B., Jahreiss, H., Wielen, R.
openaire   +4 more sources

COOL SUBDWARF INVESTIGATIONS. III. DYNAMICAL MASSES OF LOW-METALLICITY SUBDWARFS [PDF]

open access: yesThe Astronomical Journal, 2016
ABSTRACT We report dynamical mass measurements for the components of the previously known double-lined spectroscopic subdwarfs G 006-026 B and C using the Fine Guidance Sensors on the Hubble Space Telescope. To build the empirical mass–luminosity relation for low-metallicity subdwarfs, we collect four other subdwarf systems with ...
Wei-Chun 饒惟君 Jao   +4 more
openaire   +4 more sources

The subdwarf luminosity function [PDF]

open access: yesMonthly Notices of the Royal Astronomical Society, 2003
Using data from the Sloan Digital Sky Survey Early Data Release and SuperCOSMOS Sky Survey scans of POSS-I plates we identify a sample of 2600 subdwarfs using reduced proper motion methods and strict selection criteria. This forms one of the largest and most reliable samples of candidate subdwarfs known, and enables us to determine accurate luminosity ...
Digby, Andrew P.   +4 more
openaire   +2 more sources

Hot Subdwarfs in the Galactic Bulge [PDF]

open access: yesThe Astrophysical Journal, 2005
Recent observations and theories suggest that extreme horizontal branch (EHB) stars and their progeny should be the cause of the UV excess seen in the spectra of many elliptical galaxies. Since the Galactic Bulge is the closest representation of an old, metal-rich spheroid in which we are able to study the EHB scenario in detail, we obtained spectra of
Busso, Giorgia   +4 more
openaire   +3 more sources

Origin and pulsation of hot subdwarfs [PDF]

open access: yesProceedings of the International Astronomical Union, 2013
AbstractWe briefly introduce hot subdwarfs and their evolutionary status before discussing the different types of known pulsators in more detail. Currently, at least six apparently distinct types of variable are known among hot subdwarfs, encompassing p- as well as g-mode pulsators and objects in the Galactic field as well as in globular clusters. Most
Randall, Suzanna K   +4 more
openaire   +1 more source

The Formation of Subdwarf A-type Stars [PDF]

open access: yesThe Astrophysical Journal, 2019
Abstract Subdwarf A-type stars (sdAs) are objects that have hydrogen-rich spectra with surface gravity similar to that of hot subdwarf stars but effective temperature below the zero-age horizontal branch. They are considered to be metal-poor main-sequence (MS) stars or extremely low-mass white dwarfs (ELM WDs).
Jinlong Yu   +8 more
openaire   +2 more sources

FINDING EXTREME SUBDWARFS [PDF]

open access: yesThe Astronomical Journal, 2008
23 pages, 10 figures.
openaire   +2 more sources

The Formation of Subdwarf B Stars [PDF]

open access: yesInternational Astronomical Union Colloquium, 2002
AbstractWe performed full binary evolution calculations and carried out binary population synthesis studies in order to investigate the formation of subdwarf B (sdB) stars via the channels of stable Roche lobe overflow (RLOF), common envelope ejection and helium white dwarf mergers. Our model is successful in the explanation of observational properties
Han, Z   +4 more
openaire   +2 more sources

Purple dwarfs: New L subdwarfs from UKIDSS and SDSS

open access: yesEPJ Web of Conferences, 2013
The first L subdwarf was a discovered only ten years ago. Less than ten L subdwarfs been published in the literature to date. Metal-poor ultracool atmospheres has not been well understood.
Marocco F.   +7 more
doaj   +1 more source

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