Abstract
The fine structure intervals in helium have been the focus of many theoretical and experimental studies in recent years with most of them concentrating on the 1s2p 3 P J levels. Here, we report on a theoretical calculation and an experimental determination of the 1s2p 3 P J fine structure intervals. The values from the theoretical calculation are 8113.730(6) and 658.801(6) MHz for the v 01 and v 12 intervals, respectively. The laser spectroscopic measurement reported here yields 8113.714(28) and 658.810(18) MHz for these intervals and is in excellent agreement with the theoretical calculation. Both, however, disagree significantly with the previous most precise experimental results. © 2005 The American Physical Society.