MEASUREMENTS FOR SPIN INVERSION AND NONINVERSION IN SUCCESSIVE DECAYSVIA NUCLEAR-MAGNETIC-RESONANCE ON ORIENTED NUCLEI

Nuclear magnetic resonance on oriented nuclei (NMR-ON) measurements we re performed on the successive decays of Zr-89-Y-89(m) and Os-191-Ir-1 91(m) in Fe. The NMR-ON spectra of (ZrFe)-Zr-89 and (OsFe)-Os-191 were obtained by detecting gamma rays from the decay of the isomers, Y-89( m) and Ir-191(m), respectively. For (ZrFe)-Zr-89, the anisotropy of th e gamma ray increased at the resonance. On the other hand, for (OsFe)- Os-191 the anisotropy of the gamma ray decreased at the resonance. The se phenomena were explained using the spin inversion and spin noninver sion processes including the lifetimes of the isomers and spin lattice relaxation times. NMR-ON measurements for such spin inversion and non inversion processes were reported. The resonance spectra were also obs erved by detecting beta rays from Zr-89 and Os-191. In these experimen ts the magnetic moments of Zr-89 and Os-191 were determined to be -1.0 8 (2) mu(N) and 0.962 (28) mu(N), respectively. The signs of the magne tic moments of Y-89(m) and Ir-191(m) were also determined to be positi ve.