Nuclear moments of neutron-rich aluminum isotopes

Ground-state magnetic-dipole moments (μ) of 30-32Al and electric quadrupole moments (Q) of 31,32Al have been measured with the β-NMR method using spin-polarized radioactive-isotope beams produced in projectile-fragmentation reactions. Beams of 30-32Al were obtained by using RIKEN projectile-fragment separator RIPS after the fragmentation of 40Ar projectiles at an energy of E = 95A MeV on a 93Nb target. The obtained μexp[30-32Al] and \(Q_{\rm exp}[^{32}{\rm Al]}\) values agree well with shell-model calculations within the sd shell using the USD interaction. Also, Qexp[31Al] was found to be small. Thus, we can conclude that these aluminum isotopes are located outside the island of inversion.