Heidelberg 2015 – wissenschaftliches Programm
A 39.6: Vortrag
Freitag, 27. März 2015, 12:15–12:30, C/kHS
Towards solving the proton radius puzzle: Results from the Muonic Helium Lamb Shift experiment — •Marc Diepold and the CREMA Collaboration — Max-Planck-Institute of Quantum Optics, Garching
The recently completed muonic helium Lamb shift experiment located at Paul-Scherrer-Institute (Switzerland) measured different 2S→2P Lamb-shift transition frequencies in the µ4He+ and µ3He+ exotic ions by means of laser spectroscopy.
In these hydrogen-like systems all of the atom’s electrons are replaced by a single muon upon creation when negative muons are stopped in ordinary matter. The muon’s Bohr radius is 200 times smaller than the corresponding electronic Bohr radius in ordinary H-like ions due to the 200 times larger mass of the muon. This results in a large increase in sensitivity to the finite charge and magnetic radius of the nucleus.
Preliminary results are presented that will use this to determine the nuclear rms charge radii of the smallest helium isotopes ten times more accurately in the future, serving as important input parameters in both nuclear models and atomic theory.
Furthermore these findings shed new light on the so-called Proton Radius Puzzle that was created by the 7 sigma discrepancy between measurements of the proton rms charge radius in muonic hydrogen and normal hydrogen spectroscopy or electron scattering experiments.