The 'island of inversion' from a nuclear moments perspective and the g factor of Si-35

摘要

This paper reviews recent results from electromagnetic moment measurements on isotopes in the island of inversion around N=20. The obtained moments on neutron rich Na, Mg, Al and Si isotopes allow to draw conclusions on the amount of intruder components in their ground state wave function, demonstrating a gradual transition from the normal sd-shell region into the island of inversion, starting at N=18 for Na, N=19 for Mg and N=20 for Al isotopes. A measurement of the ground state g factor of Si-35 (N=21), using a polarized fragment beam at GANIL, is discussed in more detail. The magnetic moment mu(Si-35, I-pi = 7/2(-)) = (-)1.638(4) mu(N) is consistent with a normal ground state structure, dominated by a nu f(7/2) neutron.