Helium 23p fine structure measurement in a discharge cell

T. Zelevinsky*, D. Farkas, G. Gabrielse

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingChapter


A precise measurement of helium 23P fine structure was carried out in a discharge cell using Doppler-free laser spectroscopy. It is the only known experiment to directly measure all three fine structure intervals at a 1 kHz level of accuracy. The 23P1 - 23P2 interval value agrees with other experiments but disagrees with theoretical predictions of two-electron QED. When this disagreement is resolved, the 23Po - 23P1 interval measurement reported here will allow a determination of the fine structure constant to 14 parts in l09, surpassing the precision of the well known QED-independent quantum Hall effect and Josephson effect determinations. The discharge cell is shown to be advantageous in the study and correction of systematic frequency shifts related to light pressure, and the use of the cell ensures that the possible systematic errors are substantially different from those reported in other experiments.

Original languageEnglish (US)
Title of host publicationMicro, Meso, Macro
Subtitle of host publicationAddressing Complex Systems Couplings
PublisherWorld Scientific Publishing Co.
Number of pages10
ISBN (Electronic)9789812701473
ISBN (Print)9789812566591
StatePublished - Jan 1 2005

ASJC Scopus subject areas

  • Physics and Astronomy(all)


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