Abstract
We report spectroscopic results on the 2s2p^{1}P_{1} state in neutral atomic beryllium-9. The absolute frequency for the center of gravity is determined to be 42 565.4501(13) cm^{-1}, a factor of 130 more precise than the previous experimental measurement. The result is in agreement with and a factor of 8 more precise than the current best theoretical estimate of 42 565.441(11) cm^{-1}, which was calculated including the effects of quantum electrodynamics. Because of the large natural linewidth of the transition, the hyperfine constants were not able to be extracted to high precision.
Highlights
Quantum electrodynamics (QED), the relativistic quantum field theory that describes the interaction between light and matter, is one of the most tested and successful modern theories
We report a conservative center-ofgravity transition energy of 42565.4501(13) cm−1, in agreement with the latest theoretical prediction and verifying the need for inclusion of QED contributions [15]
The absolute frequency for the center of gravity for the 2s2 1S0 − 2s2p 1P1 transition agrees with the current best theoretical prediction, a confirmation of both QED and the theoretical methods used to determine the energy of the transition
Summary
Quantum electrodynamics (QED), the relativistic quantum field theory that describes the interaction between light and matter, is one of the most tested and successful modern theories. In the context of spectroscopy, testing QED typically involves a theoretical prediction of an atomic property, such as the absolute energy of a state, and an experimental verification of the prediction. Theoretical calculations of atomic properties, such as transition frequencies, generally become more difficult as the neutron, proton, and electron number increase. During the last 80 years, research on the helium and lithium atoms has served to refine various quantum mechanical methods. The Hylleraas-type quantum mechanical methods [2] have more than 40 digits accuracy and are more precise than the best experiments [3,4,5,6,7,8]. The accuracy achieved for lithium is up to 14-15 digits [9,10,11,12,13,14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
