Results 11 to 20 of about 805 (173)
Purple dwarfs: New L subdwarfs from UKIDSS and SDSS [PDF]
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 +2 more sources
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 +3 more sources
Origin and pulsation of hot subdwarfs [PDF]
Proceedings 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 +2 more sources
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 +2 more sources
Summary of Eighth Meeting on Hot Subdwarfs and Related Objects
Open Astronomy, 2017 Subjects discussed during the Eighth Meeting on Hot Subdwarfs and Related Objects are summarised. In particular, a succinct presentation is given of challenges to stellar evolution arising from recent observations.
Lynas-Gray Anthony Eugene
doaj +3 more sources
HST spectroscopy of chemically peculiar hot subdwarfs: PG 0909+276 and UVO0512–08 [PDF]
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 +2 more sources
Kinematics of nearby Subdwarfs [PDF]
Astrophysics 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 +2 more sources
Asteroseismic Observations of Hot Subdwarfs
Frontiers 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 +1 more source
The subdwarf luminosity function [PDF]
Monthly 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
COOL SUBDWARF INVESTIGATIONS. III. DYNAMICAL MASSES OF LOW-METALLICITY SUBDWARFS [PDF]
The 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 +2 more sources