Stark Effect in He II and H

The beam-foil light source was used for a study of the Stark effect on He II ($\lambda 4686$Å) and ${\mathrm{H}}_{\beta }$. For the former, the $p$ and $s$ components were detected for transverse and longitudinal fields. The transverse-field data suggest that levels of high $j$ are underpopulated relative to their equilibrium numbers. The longitudinal-field data are anomalous. For $H_{\beta }$, splitting was observed, but the arrangement precluded the detection of polarization. The data also imply underpopulation of levels of high $j$.