Spectroscopy on He-like carbon ions more than 1000 times improved

Connecting an electron beam ion source (EBIS) to our COALA beamline, we made ions from such a source for the first time accessible for collinear laser spectroscopy. Our measurements on C⁴⁺ ions have achieved a 1000-fold higher relative accuracy Δν/ν of optical transition frequencies compared to previous measurements. This paves the way for a direct determination of the nuclear charge radius with a corresponding improvement in atomic physics theory.
A corresponding dual publication has now appeared in Phys. Rev. Lett. and Phys. Rev. A and a press release is available at idw and the webpage of TU Darmstadt (in German).