Nuclear magnetic moment of the neutron-rich nucleus <math><mmultiscripts><mi mathvariant="normal">O</mi><mprescripts/><none/><mn>21</mn></mmultiscripts></math>

International audienceThe ground-state magnetic dipole moment of the neutron-rich O21 isotope has been measured via β-ray-detected nuclear magnetic resonance (β-NMR) spectroscopy by using a spin-polarized secondary beam of O21 produced from the Ne22 primary beam. From the present measurement, the g factor |gexp(Og.s.21)|=0.6036(14) has been determined. Based on the comparison of this value with Schmidt values, we unambiguously confirm the νd5/2 configuration with spin and parity assignments Iπ=5/2+ for the O21 ground state, suggested by previously reported studies. Consequently, the magnetic moment has been determined as μexp(Og.s.21)=(−)1.5090(35)μN. The obtained experimental magnetic moment is in good agreement with the predictions of the shell-model calculations using the USD, YSOX, and SDPF-M interactions as well as random phase approximation (RPA) calculations. This observation indicates that the O21 nucleus in its ground state does not manifest any anomalous structure and is not influenced by the proximity of the drip line