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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 atomic-beam laser-rf double-resonance technique has been used to make precision measurements of the hyperfine structure (hfs) splittings in the 5${\mathit{d}}^{2}$6${\mathit{s}}^{2}$ $^{3}$${\mathit{F}}_{\mathit{J}}$ (J=2\char21{}4) states in $^{177,179}\mathrm{Hf}$ i. By making corrections to the second-order hfs effects, magnetic dipole (A), electric quadrupole (B), and magnetic octupole (C) hfs constants are obtained for the $^{3}$${\mathit{F}}_{\mathit{J}}$ states in $^{177,179}\mathrm{Hf}$: The constant C has a strong J dependence as well as does A and B; the isotopic ratio of the constant A between $^{177}\mathrm{Hf}$ and $^{179}\mathrm{Hf}$ has a significant J dependence, indicating J-dependent hyperfine anomalies, while that of the constant C is independent of J within experimental uncertainties, which is taken to be the ratio of the nuclear-ground-state magnetic octupole moments \ensuremath{\Omega}, i.e., \ensuremath{\Omega}${(}^{177}$Hf)/\ensuremath{\Omega}${(}^{179}$Hf)=-0.41(9). It is also pointed out that there is a clear indication of nuclear-spin dependence of the isotopic ratios of C. The single-electron hfs parameters of the 5d electron for the 5${\mathit{d}}^{2}$6${\mathit{s}}^{2}$ configuration in Hf i are obtained, and the Sternheimer shielding factor ${\mathit{R}}_{5\mathit{d}}$=-0.397(8) is derived.

Hyperfine structure of the 5${\mathit{d}}^{3}$6${\mathit{s}}^{2}$ $^{4}$${\mathit{F}}_{3/2}$ ground state in $^{180\mathit{m}}\mathrm{Ta}$ i was precisely measured by means of atomic-beam laser-rf double-resonance spectroscopy. Hyperfine-interaction constants A and B for the ground state $^{4}$${\mathit{F}}_{3/2}$ were determined with accuracies of 3 and 10 ppm, respectively. The nuclear electric quadrupole moment was derived, as well as a precise value of the magnetic moment for $^{180\mathit{m}}\mathrm{Ta}$ (${\mathit{I}}^{\mathrm{\ensuremath{\pi}}}$=${9}^{\mathrm{\ensuremath{-}}}$): the magnetic dipole moment is ${\mathrm{\ensuremath{\mu}}}_{\mathit{I}}^{180\mathit{m}}$=+4.825(11)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$ and the spectroscopic quadrupole moment is ${\mathit{Q}}_{\mathit{s}}^{180\mathit{m}}$=+4.946(20)b.

Angular distributions of the differential cross section, analyzing power, spin-flip probability, and spin-flip asymmetry in the excitation of the first 2{sup +} states in {sup 48}Ti and {sup 50}Ti were measured at incident energies of 11 and 18 MeV using the ({ital p},{ital p}{prime}{gamma}) coincidence technique with a polarized proton beam. The angular distributions show strong incident energy and target dependence. The results were analyzed in terms of a macroscopic coupled-channels method based on the vibrational model and of the microscopic distorted wave Born approximation based on shell-model wave functions and effective nucleon-nucleon interactions. The spin-flip asymmetry is quite sensitive to the spin-dependent part in the interaction that causes inelastic scattering.

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}

The double differential cross section, the vector analyzing power, and the tensor analyzing powers for the /sup 4/He(d, p)n /sup 4/He reaction were measured at 12 and 21 MeV deuteron energy and in steps of 5/sup 0/ between 15/sup 0/ and 75/sup 0/ in the laboratory system. The experimental results are compared with the Faddeev calculations, in which three cases for the treatment of the neutron-proton interaction are tested. As a result, we can demonstrate what interaction is effective on each observable.

Measurements of the cross section, vector analyzing power, iT/sub 11/, and all three tensor analyzing powers, T/sub 20/, T/sub 21/, and T/sub 22/, have been made for the (d-arrow-right, /sup 6/Li) reactions on /sup 12/C and /sup 16/O at bombarding energies of 18 and 22 MeV. The observed large values of the tensor analyzing powers do not agree with distorted-wave Born approximation calculations assuming a one-step alpha-cluster transfer.