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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-resolution optical spectroscopy of Praesepe white dwarfs
(2009)
We present the results of a high-resolution optical spectroscopic study of nine white dwarf candidate members of Praesepe undertaken with the VLT and Ultraviolet and Visual Echelle Spectrograph. We find, contrary to a ...
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 ...
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 ...
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 ...
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 ...
Astronometry with the Hubble Space Telescope : trigonometric parallaxes of planetary nebula nuclei NGC 6853, NGC 7293, Abell 31 and DeHt 5
(2009)
We present absolute parallaxes and relative proper motions for the central stars of the planetary nebulae NGC 6853 (The Dumbbell), NGC 7293 (The Helix), Abell 31, and DeHt 5. This paper details our reduction and analysis ...
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 ...
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 ...