Study of unstable nuclear structure with radiation-detected optical pumping in solids and magnetic resonance

本课题主要研究了三个方面的内容：1)固体CaF_2和SRF_2中Tm同位素的光泵浦研究。将不稳定的Tm同位素注入到单晶CaF2中，并在固体中进行光泵浦光偏振。用大阪大学RCNP的质量分离器CARAP对同位素Tm进行了质量分离，得到的核极化约为2-4%。除了核极化外，还通过施加射频磁场观察到磁共振，从而确定了166Tm的磁矩。我们还用稳定的Tm同位素研究了注入Tm同位素的晶格位置和离子状态。2)将不稳定同位素注入到砷化镓单晶中，并在固体中进行光泵浦光偏振。114英寸在欧洲核子研究中心用质量分离器Isolde进行质量分离，然后离线极化。核极化只在一个很窄的波长范围内观察到。在800 nm附近，观察到的偏振度约为2%。我们还观察到了该波长附近的精细结构，这可能与朗道分裂有关。3)在RIKEN用质量分离器RIP进行质量分离后，将富中子的~(33)Si同位素注入到GaAs单晶中。观察到的核极化约为2%。通过施加射频磁场，获得了初步的磁矩结果。这些实验结果表明，固体中的光抽运对于研究远离稳定线的不稳定核结构具有很大的潜力。

Three topics have been investigated in this research project : 1) Study of Tm isotopes with optical pumping in solids CaF2 and SrF2. Unstable Tm isotopes were implanted into a single crystal CaF2 and polarized with the optical pumping in solids. The isotopes Tm were mass separated with the mass separator CARP at RCNP, Osaka University.The obtained nuclear polarization was about 2-4 %. In addition to the nuclear polarization, a magnetic resonance was observed by applying a rf magnetic field, thereby determined the magnetic moment of 166Tm. The lattice site and ionic states of implanted Tm isotopes we're also investigated with stable Tm isotopes. 2) Unstable In isotopes were implanted into a GaAs single crystal and polarized with optical pumping in solids. The 114In. were mass separated with the mass separator ISOLDE at CERN, and then off-line polarized. Nuclear polarization was observed only at a narrow wavelength region. around 800 nm, observed polarization being about 2%. Also we observed a fine structure around this wavelength region, which may be related to the Landau splitting. 3)The neutron rich 33Si isotopes were implanted into a GaAs single crystal after mass separated with the mass separator RIPS at RIKEN. The nuclear polarization observed was about 2%.By applying a rf magnetic field, Preliminary results on magnetic moment was obtained. These experimental results thus obtained show profound potentiality of the optical pumping in solids for the study of unstable nuclear structure far from the stability line.