The two-photon exchange contribution to muonic hydrogen from chiral perturbation theory
We compute the spin-dependent and spin-independent structure functions of the forward virtual-photon Compton tensor of the proton at using heavy baryon effective theory including the Delta particle. We compare with previous results when existing. Using these results we obtain the leading hadronic co...
| Authors: | , |
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| Format: | article |
| Publication Date: | 2014 |
| Country: | España |
| Institution: | Universidad Complutense de Madrid (UCM) |
| Repository: | Docta Complutense |
| Language: | English |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/100995 |
| Online Access: | https://hdl.handle.net/20.500.14352/100995 |
| Access Level: | Open access |
| Keyword: | 53 Proton polarizability contribution Virtual Compton-scattering Baryon axial currents Lamb shift Hyperfine structure Form-factors Low energies Nucleon Particles Radius Física (Física) 22 Física |
| Summary: | We compute the spin-dependent and spin-independent structure functions of the forward virtual-photon Compton tensor of the proton at using heavy baryon effective theory including the Delta particle. We compare with previous results when existing. Using these results we obtain the leading hadronic contributions, associated to the pion and Delta particles, to the Wilson coefficients of the lepton–proton four fermion operators in NRQED. The spin-independent coefficient yields a pure prediction for the two-photon exchange contribution to the muonic hydrogen Lamb shift, . We also compute the charge, , and Zemach, , moments for . Finally, we discuss the spin-dependent case, for which we compute the difference between the four-fermion Wilson coefficients relevant for hydrogen and muonic hydrogen. |
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