Precise measurement of magnetic moment of short-lived β-emitting nuclei 12 B ( I π =1 + , T 1/2 =20.18 ms)

The spin polarized β-emitting nuclei 12 B ( I π =1 + , T 1/2 =20.18 ms) were produced by the nuclear reaction 11 B(d, p) 12 B and by the selection technique of the incident deuteron energy and the 12 B recoil angle following the nuclear reaction. The nuclear magnetic moment of the short-lived nuclei 12 B was measured by β-NMR with the β-NMR and β-NQR setup established for the first time in China. The nuclear magnetic moment of 12 B was determined to be μ=0.99993±0.00048 nm or g =0.99993±0.00048 after the precise correction of the Knight shift.