Asymmetry observed in the stark components of H α

This paper is a report of observations on Ha which show an asymmetry in the displacements as well as in the intensities of its Stark components. The early theoretical treatments of the Stark effect in hydrogen neglected the fine structure and gave symmetrical displacements of the components in moderate electric fields (about 40,000 v./cm.). So far as the writer is aware, no observations have been made which would lead one to deny this symmetry. Using the wave equations of Darwin and Dirac, Schlapp has reconsidered the hydrogen-like atom in an external electric field and under the influence of the forces which cause fine structure. In the case of Ha numerical results were calculated for two limiting cases, (i) where the effect of the electric field is small compared with the fine structure (for fields less than 300 v./cm.), and (ii) where the fine structure is small compared with the Stark effect (fields above 10,000 v./cm.). The displacements were not calculated for the intermediate region, but the connections between the two sets of components are given.