191 citations · 828 across the 26 of their papers we have counts for
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KBS 13 -- a Rare Reflection Effect sdB Binary with an M Dwarf Secondary
B. -Q. For, H. Edelmann, E. M. Green +3
We report preliminary VRI differential photometric and spectroscopic results for KBS 13, a recently discovered non-eclipsing sdB+dM system. Radial velocity measurements indicate an…
HW Vir's Companion: a M-type Dwarf, or maybe a giant rotating spherical Mirror?
Heinz Edelmann
From optical high-resolution spectra the nature of the unseen companion of HW Vir is determined without detection of any spectral features originating from the secondary itself. Us…
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…
Binary sdB Stars with Massive Compact Companions
S. Geier, C. Karl, H. Edelmann +2
The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis…
LMC origin of the hyper-velocity star HE 0437-5439. Beyond the supermassive black hole paradigm
N. Przybilla, M. F. Nieva, U. Heber +4
Context: Hyper-velocity stars move so fast that only a supermassive black hole (SMBH) seems to be capable to accelerate them. Hence the Galactic centre (GC) is their only suggested…
Tidal synchronization of the subdwarf B binary PG 0101+039
S. Geier, S. Nesslinger, U. Heber +3
Tidally locked rotation is a frequently applied assumption that helps to measure masses of invisible compact companions in close binaries. The calculations of synchronization times…
Spectroscopic Analysis of subluminous B Stars in Binaries with compact Companions
S. Geier, C. Karl, H. Edelmann +2
The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis…
Spectroscopic Analysis of Subluminous B Stars in Binaries - Four Candidate Systems with Neutron Star/Black Hole Companions Discovered
S. Geier, C. Karl, H. Edelmann +2
The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis…
NLTE analyses of sdB stars: progress and prospects
N. Przybilla, M. F. Nieva, H. Edelmann
We report on preliminary results of a hybrid non-LTE analysis of high-resolution, high-S/N spectra of the helium-rich subdwarf B star Feige49 and the helium-poor sdB HD205805. Non-…
HE 0437-5439 -- an unbound hyper-velocity main-sequence B-type star
Heinz Edelmann, Ralf Napiwotzki, Uli Heber +2
We report the discovery of a 16th magnitude star, HE0437-5439, with a heliocentric radial velocity of +723+-3km/s. A quantitative spectral analysis of high-resolution optical spect…
High resolution spectroscopy of bright subdwarf B stars - I. Radial velocity variables
H. Edelmann, U. Heber, M. Altmann +2
Radial velocity curves for 15 bright subdwarf B binary systems have been measured using high precision radial velocity measurements from high S/N optical high-resolution spectra. I…
Atmospheric parameters and abundances of sdB stars
U. Heber, H. Edelmannn
We summarize recent results of quantitative spectral analyses using NLTE and metal line-blanketed LTE model atmospheres. Temperatures and gravities derived for hundreds of sdB star…
Studying the populations of our Galaxy using the kinematics of sdB stars
M. Altmann, H. Edelmann, K. S. de Boer
We have analysed the kinematics of a sample of 114 hot subdwarf stars, for 2/3 of which we present new proper motions, spectroscopic and photometric data. The vast majority of the…
Simultaneous time-series spectroscopy and multi-band photometry of the sdBV PG 1605+072
S. Falter, U. Heber, S. Dreizler +3
We present time-series spectroscopy and multi-band photometry of the sdBV PG 1605+072 carried out simultaneously at the Calar Alto 2.2m and 3.5m telescopes. The periodogram analysi…
Spectral analysis of sdB stars from the Hamburg Quasar Survey
H. Edelmann, U. Heber, H. -J. Hagen +4
We present the results of a spectral analysis of a large sample of subdwarf B stars selected from follow-up observations of candidates from the Hamburg Quasar Survey. Fundamental p…
Early type stars at high galactic latitudes II. Four evolved B-type stars of unusual chemical composition
M. Ramspeck, U. Heber, H. Edelmann
We present the result of differential spectral analyses of a further four apparently normal B-type stars. Abundance anomalies (e.g. He, C, N enrichment), slow rotation and/or high…