Research report 2013 - Max Planck Institute of Quantum Optics
Laser Spectroscopy of muonic atoms
Max-Planck-Institut für Quantenoptik, Garching
SummaryAn exotic type of hydrogen, where the central nucleus – a single proton – is orbited by a muon instead of an electron, permits novel studies of the proton structure. The surprising result is that the charge radius of the proton is 4% smaller than previously measured. This “proton radius puzzle” has led to many speculations, even questioning the theory of quantum electrodynamics or the Standard Model of particle physics. Scientists at MPQ hope to shed new light on the “proton radius puzzle” using laser spectroscopy of muonic deuterium atoms and muonic helium ions.