[RIBF-ULIC-Symposium-007] E(U)RICA International Workshop

g-factor measurements for highly spin-aligned isomeric states

24 May 2011, 11:45

20m

RIBF Building 2F Conference Room (RIKEN Nishina Center)

RISING and other gamma-ray measurement techniques

Speaker

Yuichi Ichikawa (RIKEN Nishina Center)

Description

The nuclear spin alignment in an excited state results in anisotropy of angular distribution in Gamma-ray emission, which provides us a chance to measure nuclear observables through various spectroscopic techniques. Especially the time-differential perturbed angular distribution (TDPAD) method is one of the major techniques to determine a g-factor of an isomeric state with a lifetime of ns - ms order, where the g-factor is determined from a time dependence of anisotropy of de-excitation Gamma rays emitted from spin-aligned nuclei precessing in an external magnetic field. In this study, we have developed a novel method to produce an RI beam with high spin-alignment, that is the two-step fragmentation method with a technique of momentum-dispersion matching. The experiment to apply the new method to study of 32Al was carried out with BigRIPS in RIKEN RIBF. The isomeric states of 32Al was produced by two-step fragmentation of a primary beam of 48Ca via 33Al, then its g-factor was determined for the first time using the TDPAD method. The experimental results will be given in the presentation.