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Hyperfine splitting in positronium to O(α(7)m(e)): one photon annihilation contribution
M Baker1, P Marquard2, A A Penin3
1Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1, Canada.
Physical Review Letters
|April 15, 2014
Summary
We calculated the O(α7me) one photon annihilation contribution to positronium hyperfine splitting. This quantum electrodynamics calculation increases predictions by 217±1 kHz.
Area of Science:
- Atomic Physics
- Quantum Electrodynamics
- Particle Physics
Background:
- Positronium is a simple atomic system composed of an electron and a positron.
- Hyperfine splitting in positronium is sensitive to fundamental physics and quantum electrodynamics (QED) effects.
- Precise theoretical predictions are crucial for comparing with experimental measurements.
Purpose of the Study:
- To compute the complete O(α7me) one-photon annihilation contribution to the ground state hyperfine splitting of positronium.
- To improve the theoretical accuracy of positronium energy levels within the framework of QED.
- To provide a benchmark for theoretical calculations and experimental verification.
Main Methods:
- Perturbative calculations in quantum electrodynamics.
- Inclusion of higher-order radiative corrections.
- Analytical and numerical evaluation of Feynman diagrams.
Main Results:
- The complete O(α7me) one-photon annihilation contribution has been determined.
- This contribution results in a numerical increase of 217±1 kHz to the predicted hyperfine splitting.
- The calculation refines the theoretical understanding of positronium energy levels.
Conclusions:
- The calculated contribution represents a significant advancement in the precision of QED predictions for positronium.
- This result enhances the agreement between theory and experiment in atomic physics.
- Further theoretical and experimental investigations are warranted to explore higher-order corrections and their impact.
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