Magnetic moments of 3013Al17 and 3213Al19

Ground-state magnetic moments of 30Al and 32Al were measured with the β-NMR method using radioactive-isotope beams spin-polarized in the projectile-fragmentation reaction. Polarization of sizes |P|=0.5-1% were obtained in spite of the large numbers of nucleons that are removed from the projectile 40Ar, providing a promising prospect that substantial polarizations are obtained even in fragment nuclei that are far removed from the projectile nucleus. The obtained μ moments, |μexp(Al30)|=3.010(7)μN and |μexp(Al32)|=1.959(9)μN, are in agreement with shell model calculations within the sd valence space, although a reduction in the energy-gap between the sd and pf states is predicted for 32Al in recent theoretical studies.