Measurement of the Fine Structure Separation 3 3P1-3 3P2 for the Helium Atom
Abstract
The fine structure of helium levels (1s3p) 3PJ, J=1, 2 is determined by the microwave-optical method outlined in the preceding paper. Helium atoms are excited to 3 3PJ by electron bombardment and the optical radiation 3 3PJ-->2 3S1(3889 A) is observed with a photomultiplier tube. The intensity of this radiation changes when radio waves induce transitions between the fine structure sublevels. The separation 3 3P1-3 3P2 is found to be 658.0+/-1.0 Mc/sec, which is to be compared to the most recent optical estimates of 750+/-300 Mc/sec.
- Publication:
-
Physical Review
- Pub Date:
- January 1957
- DOI:
- 10.1103/PhysRev.105.573
- Bibcode:
- 1957PhRv..105..573L