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Precision Spectroscopy in He as a Test of QED



S Bergeson, A Balakrishnan, K G. Baldwin, Thomas B. Lucatorto, J P. Marangos, T J. McIlrath, Thomas R. O'Brian, S L. Rolston, Craig J. Sansonetti, J Wen, N Westbrook, C H. Cheng, E E. Eyler


High resolution laser-based measurements of energy levels have spurred the development and refinement of quantum electrodynamic calculations. We have extended very high resolution laser spectroscopy techniques into the vacuum ultraviolet wavelength region at λ {approximately equal to} 120 nm to determine the Lamb shift in the ground state of He -. The importance of this measurement to high accuracy quantum electrodynamics calculations is discussed. Details of the present measurement and future improvements are presented.
Physica Scripta


helium, Lamb shift, laser spectroscopy, QED, two-photon transition, VUV


Bergeson, S. , Balakrishnan, A. , Baldwin, K. , Lucatorto, T. , Marangos, J. , McIlrath, T. , O'Brian, T. , Rolston, S. , Sansonetti, C. , Wen, J. , Westbrook, N. , Cheng, C. and Eyler, E. (1999), Precision Spectroscopy in He as a Test of QED, Physica Scripta (Accessed May 28, 2024)


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Created December 1, 1999, Updated February 17, 2017