Exciting Nucleons in Compton Scattering and Hydrogen-Like Atoms

Understand

This PhD thesis is devoted to the low-energy structure of the nucleon (proton and neutron) as seen through electromagnetic probes, e.g., electron and Compton scattering.

• The research presented here is based primarily on dispersion theory and chiral effective-field theory.
• The main motivation is the recent proton radius puzzle, which is the discrepancy between the classic proton charge radius determinations (based on electron-proton scattering and normal hydrogen spectroscopy) and the highly precise extraction based on first muonic-hydrogen experiments by the CREMA Collaboration.
• The precision of muonic-hydrogen experiments is presently limited by the knowledge of proton structure effects beyond the charge radius.