The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen (μp) with 1 ppm accuracy by means of pulsed laser spectroscopy. In the proposed experiment, the μp atom is excited by a laser pulse from the singlet to the triplet hyperfine sub-levels, and is quenched back to the singlet state by an inelastic collision with a H2 molecule. The resulting increase of...
9 pages, Few Body Systems FB21 conference; We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.; This work is supported by the Swiss National Science Foundation Projects No. 200021L_138175 and No. 200020_159755, the DFG_GR_3172/...