Results 11 to 20 of about 199 (140)
Kinematics of nearby subdwarf stars [PDF]
Astronomy & Astrophysics, 2005 We present an analysis of the space motions of 742 subdwarf stars based on the sample of Carney et al. (1994, CLLA). Hipparcos parallaxes, TYC2+HIP proper motions and Tycho2 proper motions were combined with radial velocities and metallicities from CLLA. The kinematical behavior is discussed in particular in relation to their metallicities.
Arifyanto, M. I. +3 more
openaire +2 more sources
The Formation of Subdwarf B Stars [PDF]
International 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
EPJ 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
In Pursuit of the Least Luminous Galaxies
Advances in Astronomy, Volume 2010, Issue 1, 2010., 2010 The dwarf galaxy companions to the Milky Way are unique cosmological laboratories. With luminosities as low as 10−7LMW, they inhabit the lowest mass dark matter halos known to host stars and are presently the most direct tracers of the distribution, mass spectrum, and clustering scale of dark matter.
Beth Willman, Regina Schulte-Ladbeck
wiley +1 more source
A FEROS Survey of Hot Subdwarf Stars
Open Astronomy, 2018 We have completed a survey of twenty-two ultraviolet-selected hot subdwarfs using the Fiber-fed Extended Range Optical Spectrograph (FEROS) and the 2.2-m telescope at La Silla. The sample includes apparently single objects as well as hot subdwarfs paired
Vennes Stéphane +2 more
doaj +1 more source
Subaru and Salt Spectroscopy of Chemically Peculiar Hot Subdwarfs
Open Astronomy, 2017 The majority of hot subdwarfs lie on or close to the helium main-sequence. Many have hydrogen-rich surfaces, but a substantial fraction of the hotter subdwarfs have hydrogen-depleted or hydrogen-deficient surfaces. Amongst the former, three were known to
Jeffery C. Simon +4 more
doaj +1 more source
X-ray emission from hot subdwarfs with compact companions
EPJ Web of Conferences, 2013 We review the X-ray observations of hot subdwarf stars. While no X-ray emission has been detected yet from binaries containing B-type subdwarfs, interesting results have been obtained in the case of the two luminous O-type subdwarfs HD 49798 and BD + 37°
Esposito P. +3 more
doaj +1 more source
HST spectroscopy of chemically peculiar hot subdwarfs: PG 0909+276 and UVO0512–08
Open Astronomy, 2017 High-resolution ultraviolet spectroscopy of two chemically peculiar hot subdwarfs, PG 0909+276 and UVO0512-08, has been obtained using the Hubble Space Telescope.
Wild James, Jeffery Christopher Simon
doaj +1 more source
Hot subdwarfs in resolved binaries [PDF]
Astrophysics and Space Science, 2010 6 pages, 4 figures. Proceedings of The Fourth Meeting on Hot Subdwarf Stars and Related Objects held in China, 20-24 July 2009.
openaire +2 more sources
The discovery of a T6.5 subdwarf [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 We report the discovery of ULAS J131610.28+075553.0, a sdT6.5 dwarf in the UKIDSS Large Area Survey 2 epoch proper motion catalogue. This object displays significant spectral peculiarity, with the largest yet seen deviations from T6 and T7 templates in the Y and K bands for this subtype.
B. Burningham +6 more
openaire +4 more sources