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Testing Quantum Electrodynamics: High Precision X-ray Spectroscopy of Muonic Neon Atoms



Douglas Bennett, W.Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Kelsey Morgan, Galen O'Neil, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Takuma Okumura


To test the bound-state quantum electrodynamics (BSQED), we have performed high precision x- ray spectroscopy of the 5g→4f and 5f→4d transitions (BSQED contribution of 2.4 eV and 5.2 eV, respectively) of muonic neons in the low-pressure gas phase under the condition without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions vanish. We determined the 5g9/2→4f7/2 transition energy to be 6297.27 eV (statistical error: 0.04 eV, systematic error: 0.13 eV) using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most-advanced BSQED theoretical prediction of 6297.26 eV.
Physical Review Letters


Bennett, D. , Doriese, W. , Durkin, M. , Fowler, J. , Gard, J. , Hilton, G. , Morgan, K. , O'Neil, G. , Reintsema, C. , Schmidt, D. , Swetz, D. , Ullom, J. and Okumura, T. (2023), Testing Quantum Electrodynamics: High Precision X-ray Spectroscopy of Muonic Neon Atoms, Physical Review Letters, [online],, (Accessed May 29, 2023)
Created April 27, 2023, Updated April 28, 2023