A 303-MHz hyperfine transition in the ground state of 9Be+ was used as a basis of a frequency standard. The ions were stored in a Penning ion trap. Linewidths as narrow as 900μHz were obtained. The frequency stability was measured to be better than 3 x 10 -12 τ -1/2 . The inaccuracy in the second-order .Doppler shift was reduced to 5 parts in 10 15 by laser cooling. An apparent pressure shift with an unexpectedly large value was discovered which limits the accuracy of the current experiment to approximately 1 part in 10 13 .
No takes yet. Share an insight, caveat, or question.
Bollinger et al. (1991) studied this question.
Synapse has enriched 3 closely related papers on similar clinical questions. Consider them for comparative context: