Abstract
We have performed calculations of the size of the frequency shift induced by a static electric field on the clock transition frequencies of the hyperfine splitting in , Rb, Cs, , and . The calculations are used to find the frequency shifts due to blackbody radiation which are needed for accurate frequency measurements and improvements of the limits on variation of the fine-structure constant . Our result for Cs is in good agreement with early measurements and ab initio calculations. We present arguments against recent claims that the actual value might be smaller. The difference is due to the contribution of the continuum spectrum in the sum over intermediate states.
- Received 18 May 2006
DOI:https://doi.org/10.1103/PhysRevA.74.023405
©2006 American Physical Society