© 2017, The Author(s). We obtain a model-independent prediction for the two-photon exchange contribution to the hyperfine splitting in muonic hydrogen. We use the relation of the Wilson coefficients of the spin-dependent dimension-six four-fermion operator of NRQED applied to the electron-proton and to the muon-proton sectors. Their difference can be reliably computed using chiral perturbation theory, whereas the Wilson coefficient of the electron-proton sector can be determined from the hyperfine splitting in hydrogen. This allows us to give a precise model-independent determination of the Wilson coefficient for the muon-proton sector, and consequently of the two-photon exchange contribution to the hyperfine splitting in muonic hydrogen, which reads δE¯pμ,HFTPE(nS)=−1n31.161(20) meV. Together with the associated QED analysis, we obtain a prediction for the hyperfine splitting in muonic hydrogen that reads E pμ,HFth (1S) = 182.623(27) meV and E pμ,HFth (2S) = 22.8123(33) meV. The error is dominated by the two-photon exchange contribution.
|Journal||Journal of High Energy Physics|
|Publication status||Published - 1 Apr 2017|
- Chiral Lagrangians
- Effective Field Theories
- Precision QED