Description
Recent progress in laser and x-ray spectroscopy of muonic atoms offers promising long-term possibilities at the intersection of atomic, nuclear and particle physics. The planned experimental program will further improve on the precision of nuclear charge radii. Laser spectroscopy measurements will determine the ground-state hyperfine splitting (HFS) of muonic hydrogen and additionally improve the Lamb shift by a factor of 5. Precision spectroscopy with cryogenic microcalorimeters has the potential to significantly improve the charge radii of the light nuclei in the Z = 3 − 8 range. Complementary progress in precision should be achieved on the theory of nucleon- and nuclear-structure effects. The impact of this muonic-atom spectroscopy program will be amplified by the upcoming results from H and He+ spectroscopy, simple molecules such as HD+ and Penning trap measurements. In this broader context, one can test ab-initio nuclear theories, bound-state QED for two- or three-body systems, and determine fundamental constants, such as the Rydberg (R∞) and the fine- structure (α) constants