57 citations · 201 across the 11 of their papers we have counts for
4 papers · 1 filter
Low-mass stellar and substellar companions to sdB stars
S. Geier, L. Classen, P. Bruenner +9
It has been suggested that besides stellar companions, substellar objects in close orbits may be able to trigger mass loss in a common envelope phase and form hot subdwarfs. In an…
Rotational properties of single and wide binary subdwarf B stars
S. Geier, U. Heber, H. Edelmann +2
We measured projected rotational velocities of more than a hundred apparently single sdBs. A comparison is made with sdB stars in binary systems with orbits so wide, that tidal int…
Helium abundances and the helium isotope anomaly of sdB stars
S. Geier, U. Heber, H. Edelmann +5
Helium abundances and atmospheric parameters have been determined from high resolution spectra for a new sample of 46 bright hot subdwarf B (sdB) stars. The helium abundances have…
Analysis of Two Eclipsing Hot Subdwarf Binaries with a Low Mass Stellar and a Brown Dwarf Companion
V. Schaffenroth, S. Geier, U. Heber +6
The formation of hot subdwarf stars (sdBs), which are core helium-burning stars located on the extended horizontal branch, is still not understood. Many of the known hot subdwarf s…