191 citations · 517 across the 14 of their papers we have counts for
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Analysis of the Hydrogen-rich Magnetic White Dwarfs in the SDSS
Baybars Külebi, Stefan Jordan, Fabian Euchner +2
We have calculated optical spectra of hydrogen-rich (DA) white dwarfs with magnetic field strengths between 1 MG and 1000 MG for temperatures between 7000 K and 50000 K. Through a…
Hypervelocity Stars: Young and Heavy or Old and Light?
Uli Heber, Heiko Hirsch, Heinz Edelmann +4
The first three hyper-velocity stars (HVS) unbound to the Galaxy were serendipitously discovered in 2005. The only suggested origin of hyper-velocity stars is the Galactic Centre a…
Subdwarf O Stars from SDSS and SPY
H. A. Hirsch, U. Heber, S. J. O'Toole
We present the results of quantitative spectral analysis of sdOs from the SDSS database. Fitting the Balmer, HeI and HeII lines to non-LTE model spectra, we derived their effective…
Searching for Hyper-Velocity Stars
A. Tillich, U. Heber, H. Hirsch
We present our survey for subluminous hyper-velocity candidates, which has been successfully initiated at the ESO NTT and the Calar Alto 3.5 m telescope.
Hot subluminous O stars from the SDSS
H. A. Hirsch, U. Heber, S. J. O'Toole
We carried out a quantitative spectral analysis of 73 hot subluminous O-stars selected from the SDSS spectral database. While the helium deficient sdOs are scattered over a wide ra…
US 708 - An unbound hyper-velocity subluminous O star
H. A. Hirsch, U. Heber, S. J. O'Toole +1
We report the discovery of an unbound hyper-velocity star, US 708, in the Milky Way halo, with a heliocentric radial velocity of +708+-15km/s. A quantitative NLTE model atmosphere…