T. Iwakoshi

A Possible Nuclear Spin Dewar. Hyperfine Interactions of Short-Lived β Emitter 8Li and 12B in TiO2

It was confirmed by detecting the β-NMR of 12B (Iπ=1+, T1/2=20.2 ms) in a TiO2 (rutile) crystal that the nuclear spin polarization of 12B was totally maintained in the crystal as produced through a nuclear reaction before implantation. Two locations, site 1 and site 2, were found with the relative populations 9 and 1, respectively, and the electric field gradients (EFGs) at those sites were obtained to be q(site 1)=+(37.1±0.5)1015 V/cm2, η(site 1)<0.03, q(site 2)=+(185±5)1015 V/cm2 and η(site 2)=0.62±0.02. We also found that about 30% of the initial polarization of 8Li (Iπ=2+, T1/2=838 ms) was maintained in the crystal. Since the polarizations of other β emitting nuclei, 12,16N, 13,19O, and 41Sc were also totally maintained in the crystal, the crystal can be a “Spin Dewar” in which many short-lived nuclides can be implanted with their polarizations totally maintained during their lifetimes for the studies not only on the electronic structure of impurities in it but also on the nuclear properties.

Test of the conserved vector current hypothesis by a β -ray angular distribution measurement in the mass-8 system

The

G-parity irregular current in the β decays of the mass A = 12 system - with the refined empirical value of the weak magnetism -

\ensuremath{\beta}

Nuclear Spin Alignment of 12,13B Produced in Heavy Ion Collisions

-ray angular correlations for the spin alignments of

Search for the G‐parity violation of weak nucleon current in β decays of mass 8 system

^{8}\mathrm{Li}

New limit of the G-parity irregular weak nucleon current detected in β decays of spin aligned 12B and 12N

and

New limit of the G parity irregular weak nucleon current detected in beta decays of spin aligned B-12 and N-12

^{8}\mathrm{B}

Electric quadrupole moment of the proton halo nucleus 8Β

have been observed in order to test the conserved vector current (CVC) hypothesis. The alignment correlation terms were combined with the known

Low-energy test of second-class current in β decays of spin-aligned 20 Fa nd 20 Na

\ensuremath{\beta}

Precise nuclear moments of 13B and the β-ray angular distribution

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