Structure of the Line λ4686 of He II

The fine structure of the line He II λ4686 was measured, and it was found that the shift of the 3 S term relative to the 3 2 P 1 / 2 term is 0.135±0.005 cm -1 . This is to be compared with the calculated value 0.138±0.001 cm -1 . That of the 4 S term was found to be 0.056±0.009 cm -1 , the calculated value being 0.0584±0.0005 cm -1 .