Recent Developments in Measurement Techniques for Magnetic Moments of Short-Lived Nuclear States

Abstract

Until some four years ago, magnetic moment measurements were confined, with few exceptions, to excited nuclear states with lifetimes longer than ∼ 10-11 s. This had to do with the problem of generating sufficiently intense fields (H ≳ 10 MGauss) at the nucleus, in controlled and quantitatively understood experimental conditions. The possibilities afforded by systems of isolated ions in this respect have since been explored by at least ten different research groups, applying a variety of techniques. The latest developments are outlined, an appraisal of certain methods is attempted and a compilation of recently determined magnetic moments appended.

Atomic spin precessions of fluorine ions recoiling through vacuum in weak transverse magnetic fields

“…Q4" G2g(T) ---0.395 (10). 4 With the assumed exponential time dependence of the perturbation in Ag the time constant 1/22Ag~--1/22g--~l/2=610(90) ns was evaluated. This result strongly favours quadrupole interactions as the dominating source of perturbation which was also found in earlier measurements [15,16].…”

“…The attenuation in the stopper foil had to be the same as that observed with thick targets since the same foil sample was used for both measurements. (2) and (4) to the data The data, corrected for small decentering of the recoil-stopper were fitted to (4) and are shown in Fig. 5.…”

“…Since it is not yet possible to obtain the fields for multi-electron ion configurations from first principle calculations it is necessary to calibrate them. In contrast, for H-like ions, which are easily obtainable for light elements the HFI are well understood [2][3][4]. A variety of experimental methods has been used to unveil the complex HFI from multi-electron configurations [-1].…”