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We present a precise measurement of the cross section, proton and 3He analyzing powers, and spin correlation coefficient Cy,y for the p-3He elastic scattering near 65 MeV, and comparison with rigorous four-nucleon scattering calculations based on realistic nuclear potentials and a model with Δ-isobar excitation. Clear discrepancies are seen in some of the measured observables in the regime around the cross section minimum. Theoretical predictions using scaling relations between the calculated cross section and the 3He binding energy are not successful in reproducing the data. Large sensitivity to the NN potentials and rather small Δ-isobar effects in the calculated cross section are noticed as different features from those in the deuteron-proton elastic scattering. The results obtained above indicate that p-3He scattering at intermediate energies is an excellent tool to explore the nuclear interactions not accessible by the three-nucleon scattering.

We have made high-resolution laser spectroscopy of the hyperfine structure of a radioactive isotope $^{179}\mathrm{Ta}$ (${T}_{\frac{1}{2}}=1.8$ y) using an argon-ion sputtering atomic-beam source. From hyperfine constants $A$ and $B$ of the atomic ground state ($^{4}F_{\frac{3}{2}}5{d}^{3}6{s}^{2}$), the magnetic dipole and electric quadrupole moments of the nuclear ground state of $^{179}\mathrm{Ta}(I=\frac{7}{2})$ have been determined for the first time: ${\ensuremath{\mu}}_{I}^{179}=2.289(9){\ensuremath{\mu}}_{N}$ and ${Q}_{s}^{179}=3.37(4)$ b. It is pointed out that magnetic moments of the ground and isomeric states in the region $N=102\ensuremath{-}112$ can be systematically described in terms of the presently available theory while the revealed systematic behavior of electric quadrupole moments is hardly reproduced by the theory.

The vector analyzing power has been measured for the elastic scattering of neutron-rich 6He from polarized protons at 71 MeV/nucleon making use of a newly constructed solid polarized proton target operated in a low magnetic field and at high temperature. Two approaches based on local one-body potentials were applied to investigate the spin-orbit interaction between a proton and a 6He nucleus. An optical model analysis revealed that the spin-orbit potential for 6He is characterized by a shallow and long-ranged shape compared with the global systematics of stable nuclei. A semimicroscopic analysis with a alpha+n+n cluster folding model suggests that the interaction between a proton and the alpha core is essentially important in describing the p+6He elastic scattering. The data are also compared with fully microscopic analyses using non-local optical potentials based on nucleon-nucleon g-matrices., 20 pages, 20 figures, accepted by Physical Review C

Vector analyzing power for the proton-{sup 6}He elastic scattering at 71 MeV/nucleon has been measured for the first time, with a newly developed polarized proton solid target, which works at a low magnetic field of 0.09 T. The results are found to be incompatible with a t-matrix folding model prediction. Comparisons of the data with g-matrix folding analyses clearly show that the vector analyzing power is sensitive to the nuclear structure model used in the reaction analysis. The {alpha}-core distribution in {sup 6}He is suggested to be a possible key for understanding the nuclear structure sensitivity.

The half-life and the magnetic moment were measured for the first excited state in $^{132}\mathrm{I}$, of which the inconsistent results on the half-life have been reported by several other groups. This time, measurements were performed on $^{132}\mathrm{I}$ obtained as a decay product of a $^{132}\mathrm{Te}$ radioactive beam from the ion guide at Tohoku University. The half-life of this level was determined to be ${T}_{1/2}=1.120\ifmmode\pm\else\textpm\fi{}0.015$ ns using a conventional coincidence technique with a pair of BaF${}_{2}$ detectors. The time-differential perturbed angular correlation technique was successfully applied to the first excited state in $^{132}\mathrm{I}$ implanted into nickel foils. The magnetic moment of this state was determined to be $\ensuremath{\mu}=+(2.06\ifmmode\pm\else\textpm\fi{}0.18){\ensuremath{\mu}}_{N}$. The present results are consistent with values reported by Gorodetzky et al. and Singh et al.

We measured the differential cross section and the spin correlation parameter C{sub yy} of the p-vector+{sup 3}He-vector elastic backward scattering at 200, 300, and 400 MeV at {theta}=180 deg. in the center-of-mass frame to study the mechanism of the reaction and to examine the validity of the {sup 3}He wave functions based on two different realistic two-body forces. This is the first measurement of the spin correlation parameter C{sub yy} of the p-vector+{sup 3}He-vector EBS at intermediate energies. The experimental results were compared with few-body calculations, including three reaction mechanisms: two-nucleon-pair exchange, pion exchange, and direct pp scattering. It was found that few-body calculations describe the differential cross-section data reasonably well. The spin correlation parameter C{sub yy} shows clear evidence for the two-nucleon-pair exchange processes in the reaction, demonstrating that the spin observables are helpful for deeper understanding of the reaction mechanism.

The hyperfine structure of the radioactive isotope {sup 175}Hf has been measured by means of laser spectroscopy. The magnetic dipole and electric quadrupole moments of {sup 175}Hf are determined: {ital {mu}{sub I}={minus}0.62(3){mu}{sub N}} and {ital Q{sub s}}=+2.6(2) b; the sign of {mu}{ital {sub I}} has been shown to be negative. It has been shown that {sup 175}Hf has almost the same nuclear charge radius as {sup 174}Hf. {copyright} {ital 1997} {ital The American Physical Society}