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Measurement of the 2P1/2–2P3/2 fine structure splitting in fluorine-like Kr, W, Re, Os and Ir



Galen O'Neil, Samuel C. Sanders, Paul Szypryt, Dipti Goyal, Amy Gall, Yang Yang, Samuel M. Brewer, W.Bertrand (Randy) Doriese, Joseph Fowler, Daniel Swetz, Joseph N. Tan, Joel Ullom, Andrey V. Volotka, Endre Takacs, Yuri Ralchenko


Quantum electrodynamics (QED) is currently considered to be one of the most accurate theories of fundamental interactions. As its extraordinary precision offers unique scientific opportunities, e.g., search for new physics, stringent experimental tests of QED continue to be of high importance. To this end, highly charged ions represent an exceptional testbed due to enhanced QED effects. Recently, forbidden transitions in F-like ions have been analyzed to few ppm precision, resolving previous discrepancies between theory and experiment. Here we further test the accuracy of QED calculations with three new (Re, Os, Ir), and two improved (Kr, W) measurements of the 2P1/2-2P3/2 transition energy in F-like ions using the NIST electron beam ion trap and extreme-ultraviolet and x-ray spectrometers. Good agreement between theoretical and experimental energies is found for all considered elements.
Physical Review A


Quantum electrodynamics, fine structure splitting, electron beam ion trap, x-ray spectrometers


O'Neil, G. , Sanders, S. , Szypryt, P. , Goyal, D. , Gall, A. , Yang, Y. , Brewer, S. , Doriese, W. , Fowler, J. , Swetz, D. , Tan, J. , Ullom, J. , Volotka, A. , Takacs, E. and Ralchenko, Y. (2020), Measurement of the 2P1/2–2P3/2 fine structure splitting in fluorine-like Kr, W, Re, Os and Ir, Physical Review A, [online], (Accessed July 18, 2024)


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Created September 2, 2020, Updated January 26, 2023