Nuclear polarization of short-lived Na isotopes maintained in single crystals for β-NMR spectroscopy

摘要

A compact β-ray detecting nuclear magnetic/quadrupole resonance system with a permanent magnet was developed at ISAC/TRIUMF to measure ground-state electromagnetic moments of short-lived nuclei. Polarized Na beams produced using the collinear optical-pumping technique were used to demonstrate the properties of the system. The degree of nuclear polarization and the spin-lattice relaxation times of the ~(20,21,26,27,28)Na isotopes in NaF, TiO_2, LiNbO_3, MgF_2, ZnO, Pt, and Mg single crystals at room temperature are reported. The electric-quadrupole coupling constants of ~(20,21)Na in TiO_2, ZnO and Mg, and that of ~(27)Na in ZnO are also reported. The quadrupole moments of ~(20,21)Na were extracted from the electric-quadrupole coupling constants in ZnO, using the known quadrupole moment of ~(27)Na.