[paper] Quadrupole moments of neutron-deficient ^20,21Na

Quadrupole moments of neutron-deficient ^20,21Na

K. Minamisono et al.

doi: 10.1016/j.physletb.2009.01.006

The electric-quadrupole coupling constant of the ground states of the proton drip line nucleus ²⁰Na (I^π=2⁺, T_1/2=447.9 ms) and the neutron-deficient nucleus ²¹Na (I^π=3/2⁺, T_1/2=22.49 s) in a hexagonal ZnO single crystal were precisely measured to be |eqQ/h|=690±12 kHz and 939±14 kHz, respectively, using the multi-frequency β-ray detecting nuclear magnetic resonance technique under presence of an electric-quadrupole interaction. An electric-quadrupole coupling constant of ²⁷Na in the ZnO crystal was also measured to be |eqQ/h|=48.4±3.8 kHz. The electric-quadrupole moments were extracted as |Q(²⁰Na)|=10.3±0.8 efm² and |Q(²¹Na)|=14.0±1.1 efm², using the electric-coupling constant of ²⁷Na and the known quadrupole moment of this nucleus as references. The present results are well explained by shell-model calculations in the full sd-shell model space.

Tags: 20Na21Naelectric quadrupole momentshell model