1996A&A...314..700F

We investigated the stationary lines of the hydrogen atom in external magnetic and electric fields relevant to white dwarf stars, by calculating the wavelengths and the oscillator strengths of the extrema of all stationary components of the Lyman α, the Balmer α and the Balmer β transitions. The results are compared with the diamagnetic hydrogen atom and the differences due to the additional electric field are investigated. Whereas the Lyman α transitions are rather insensitive to the electric field, it is shown that it exerts a considerable influence on the Balmer transitions. Moreover, we investigated the formation of further stationary components caused by a symmetry break due to the additional electric field. Our calculations cover the whole range of magnetic field strengths relevant to white dwarf stars: they extend up to B≃10⁵Tesla, the highest magnetic field strength confirmed so far.