Send to:

Choose Destination
See comment in PubMed Commons below
Phys Rev Lett. 2004 Jan 16;92(2):023001. Epub 2004 Jan 15.

Absolute frequency measurements of the 2(3)S1-->2(3)P 0,1,2 atomic helium transitions around 1083 nm.

Author information

  • 1Istituto Nazionale di Ottica Applicata (INOA), Largo E. Fermi 6, I-50125 Firenze, Italy.

Erratum in

  • Phys Rev Lett. 2006 Sep 29;97(13):139903.


We measure the frequency of the 2(3)S1-->2(3)P(0,1,2) transitions of helium in a metastable beam using an optical frequency comb synthesizer. The relative uncertainty of these measurements ranging from 5x10(-11) to 7x10(-12) is, to our knowledge, the most precise result for any optical helium transition. Considering existing accurate values of the 2(3)P fine structure, we measure a centroid value of the 2(3)S-2(3)P frequency of 276 736 495 624.6(2.4) kHz, improving the previous interferometric measurement by 30 times. New accurate values of the 2(3)S-2(3)P and 2(3)P Lamb-shift energies are obtained.

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for American Physical Society
    Loading ...
    Write to the Help Desk