Dye laser saturation spectroscopy with beams of atoms and ions

Two experiments are reported, which have been carried out applying the method of dye laser saturation spectroscopy with observation of resonance fluorescence. In the first experiment the calcium intercombination line was used for measurements of isotope shifts and hyperfine structure splittings of stable and radioactive Ca-isotopes. Previously unknown results about nuclear charge radii and quadrupole moments of Ca-isotopes were obtained. The second experiment aims for a precise determination of the fine and hyperfine structure of the first excited 3S and 3P states of the helium-like ion Li+. This experiment contributes new data to the quantum-mechanical problem of two-electron systems. (KBE)