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High resolution UVES/VLT spectra of white dwarfs observed for the ESO SN Ia Progenitor Survey III. DA white dwarfs
(2009-10)
Context. The ESO Supernova Ia Progenitor Survey (SPY) took high-resolution spectra of more than 1000 white dwarfs and pre-white dwarfs. About two thirds of the stars observed are hydrogen-dominated DA white dwarfs. Here ...
High spatial resolution Galactic 3D extinction mapping with IPHAS
(2009)
We present an algorithm (MEAD, for ‘Mapping Extinction Against Distance’) which will determine intrinsic (r′−i′) colour, extinction, and distance for early-A to K4 stars extracted from the IPHAS r′/i′/Hα photometric data ...
A new detailed examination of white dwarfs in NGC 3532 and NGC 2287
(2009)
We present the results of a photometric and spectroscopic study of the white dwarf candidate members of the intermediate age open clusters NGC 3532 and NGC 2287. Of the nine objects investigated, it is determined that six ...
RAT J1953+1859: a dwarf nova discovered through high amplitude QPOs in quiescence
(2009)
We report the discovery of an accreting binary, RAT J1953+1859, made during the RApid Temporal Survey (RATS) on the Isaac Newton Telescope. It showed high amplitude (0.3 mag) quasi-periodic oscillations on a time-scale of ...
Subdwarf B and O stars : which evolutionary pathways?
(2009)
Hot subdwarf stars (spectral types subdwarf B and O) are long lived stars producing a large amount of UV radiation. This makes them excellent candidates to explain the UV radiation observed in old populations. However, the ...
A survey for post-common-envelope binary stars using GALEX and SDSS photometry
(2009)
We report the first results of our programme to obtain multi-epoch radial velocity measurements of stars with a strong far-ultraviolet excess to identify post-common-envelope binaries (PCEBs). The targets have been identified ...
The UV-excess survey of the northern galactic plane
(2009)
The UV-Excess survey of the northern Galactic plane images a 10°× 185° wide band, centred on the Galactic equator using the 2.5-m Isaac Newton Telescope in four bands ( U, g, r, He i 5875) down to ∼21–22 mag ( ~20 in He i ...
The age of white dwarf companions
(2009)
We carried out a spectroscopic investigation of single lined white dwarfs (WDs) in double degenerate (DD) systems and discuss their binary evolution. Simulated spectra of the Hα region are used to derive upper limits on ...
The galactic population of white dwarfs
(2009)
The contribution of white dwarfs of the different Galactic populations to the stellar content of our Galaxy is only poorly known. Some authors claim a vast population of halo white dwarfs, which would be in accordance with ...
Central stars of planetary nebulae in SDSS and IPHAS
(2009)
Space densities and birthrates of Planetary Nebulae (PNe) are highly uncertain. A large range of formation rates has been derived by different studies, which has led to contradicting ideas for the final evolutionary phases ...