24 citations · 35 across the 10 of their papers we have counts for
10 papers
Gravity-induced birefringence within the framework of Poincare gauge theory
Oliver Preuss, Sami K. Solanki, M. P. Haugan +1
Gauge theories of gravity provide an elegant and promising extension of general relativity. In this paper we show that the Poincaré gauge theory exhibits gravity-induced birefringe…
Kilo-gauss Magnetic Fields in three DA White Dwarfs
R. Aznar Cuadrado, S. Jordan, R. Napiwotzki +3
We have detected longitudinal magnetic fields between 2 and 4kG in three normal DA white dwarfs (WD0446-790, WD1105-048, WD2359434) out of a sample of 12 by using optical spectr…
Constraining Gravitational Theories by Observing Magnetic White Dwarfs
Oliver Preuss, Stefan Jordan, Mark P. Haugan +1
Under the assumption of a specific nonminimal coupling of torsion to Under the assumption of a specific nonminimal coupling of torsion to electromagnetism, spacetime is birefringen…
Gaia First Look
S. Jordan, U. Bastian, H. Lenhardt +3
A complicated and ambitious space mission like Gaia needs a careful monitoring and evaluation of the functioning of all components of the satellite. This has to be performed on dif…
Discovery of magnetic fields in CPNs
S. Jordan, K. Werner, S. J. O'Toole
For the first time we have directly detected magnetic fields in central stars of planetary nebulae by means of spectro-polarimetry with FORS1 at the VLT. In all four objects of our…
Do Magnetic Fields Prevent Hydrogen from Accreting onto Cool Metal-line White Dwarf Stars?
S. Friedrich, S. Jordan, D. Koester
It is generally assumed that metals detected in the spectra of a few cool white dwarfs cannot be of primordial origin and must be accreted from the interstellar medium. However, th…