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Muon loop light-by-light contribution to hyperfine splitting in muonium
Michael I Eides1, Valery A Shelyuto2
1Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA and Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300, Russia.
Physical Review Letters
|May 20, 2014
Summary
Calculations of three-loop corrections to muonium hyperfine splitting are complete. This includes all light-by-light scattering contributions, finalizing theoretical predictions for this fundamental property.
Area of Science:
- Quantum Electrodynamics (QED)
- Atomic Physics
- Particle Physics
Background:
- Muonium is a fundamental exotic atom composed of an electron and a muon.
- Hyperfine splitting in muonium is a sensitive probe of fundamental physics.
- Previous calculations have addressed various contributions to muonium's hyperfine structure.
Purpose of the Study:
- To complete the theoretical calculation of three-loop corrections to muonium hyperfine splitting.
- To incorporate all light-by-light scattering contributions to this precision observable.
- To provide a more accurate theoretical prediction for muonium hyperfine splitting.
Main Methods:
- Calculation of gauge-invariant Feynman diagrams.
- Inclusion of muon and tauon loop light-by-light scattering blocks.
- Perturbative expansion in quantum electrodynamics.
Main Results:
- The three-loop corrections from specific gauge-invariant diagrams have been computed.
- All light-by-light scattering contributions to the hyperfine splitting have been determined.
- This completes a significant part of the theoretical calculation for muonium.
Conclusions:
- The calculation of three-loop corrections to muonium hyperfine splitting is now complete.
- This work finalizes the light-by-light scattering contributions, enhancing theoretical precision.
- The results are crucial for comparing theory with experimental measurements of muonium.
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