Study of nuclear structure for Mg isotopes via measurement of magnetic moment in excited states

为了了解富中子区出现异常核结构的机制，对报道异常核结构的^<32> Mg的邻核之一^<32> Al的同分异构体激发态的核磁矩进行了测量。本研究还提出了一种在放射性同位素（RI）光束中产生自旋对准的创新方法，即动量-色散匹配的两步碎裂法。在RIKEN RIBF的实验中，我们应用新方法成功地产生了^<32> Al的自旋取向率为8(1)%的RI束流，并首次测定了^<32> Al的异构体态的核磁矩。

In order to understand the mechanism that anomalous nuclear structure appears in the neutron-rich region, the measurement of the nuclear magnetic moment for the isomeric excited state of^<32> Al, one of the neighboring nuclei of^<32> Mg for which anomalous nuclear structure was reported, was carried out. An innovative method to produce spin alignment in radioactive-isotope(RI) beams, the two-step fragmentation method with momentum-dispersion matching, was also developed in this study. In the experiment at RIKEN RIBF, we have succeeded to produce the RI beam of^<32> Al with 8(1)% of spin alignment by applying the new method as well as to determine the nuclear magnetic moment of the isomeric state of^<32> Al for the first time.