Isomer separation and measurement of nuclear moments with the ISOLDE RILIS

Short-lived radioisotopes are element selectively ionized by the resonance ionization laser ion source (RILIS) of the on-line isotope separator ISOLDE (CERN). The relative production of low- and high-spin isomers can be signi ficantly changed when a narrow-bandwidth laser is used to scan through the atomic hyperfine structure. This allows the assignment of gamma ray transit ions to the decay of the individual isomers. Moreover, the measurement of t he hyperfine splitting provides a very sensitive method for the determinati on of magnetic moments of exotic isotopes. The technical developments are d iscussed for the example of copper.