Investigating the Proton Structure: The FAMU Experiment

The exploration of atomic structure has greatly advanced the progression toward the vision of modern physics. Thus, it is not unexpected that atoms are still being thoroughly studied, both theoretically and experimentally. Early time atomic spectroscopy allowed the unveiling of the relations describing electrons in the atomic system but also assessing the nuclear structure, giving rise to the progressive estab- lishing of the quantum field theory describing the interrela- tion between a nucleus and the bound particles, quantum electrodynamics (QED) the most successful physics theory. In the study of the simplest atom, hydrogen, the description of the nucleus, the proton, and its interaction with the orbit- ing electron are at stake. A flow of theory hypotheses and experimental verification would occur if measurements and theory predictions conflict, leading unavoidably to a novel and deeper understanding of the system.