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The SHARAQ spectrometer and High-Resolution Beamline, which began operation in March 2009, have been put into use for six experiments using charge exchange reactions with radioactive isotope beams. For experiments at SHARAQ, detector developments and ion optics studies continue to improve performance in high-resolution nuclear spectroscopy. We have introduced improved timing resolution with CVD diamond detectors, high count-rate beamline tracking detectors and development of multi-particle detection by cathode-readout drift chambers. Ion-optics studies for the high-resolution achromatic (HA) and dispersion-matching (DM) transport modes are also reported here. Momentum tagging in the HA mode demonstrated an improvement in spectroscopic resolution with respect to the momentum spread of the radioactive beam. For the DM transportation mode, a momentum resolution of 1 / 8100 (FWHM) was achieved by taking into account the positions and angles of the beam at the third focal plane of BigRIPS.

Cross section, tensor analyzing power T 20 , and vector polarization correlation coefficient C y , y for the 3 He( d , p ) 4 He reaction have been measured at 0° and E d =140, 200, and 270 MeV. The data are compared with a calculation based on an impulse approximation taking the D-state admixtures in deuteron, 3 He, and 4 He explicitly into account. The reasonable agreement with the data is understood as a consequence of a close connection between the 3 He( d , p ) 4 He reaction and the d + N backward scattering.

The deuteron single and double spin-flip probabilities, S1 and S2, have been measured for the 12C(pol{d},pol{d}') reaction at Ed = 270 MeV for an excitation energy range between 4 and 24 MeV and a scattering angular range between Theta_lab = 2.5 and 7.5 deg. The extracted S1 exhibits characteristic values depending on the structure of the excited state. The S2 is close to zero over the measured excitation energy range. The SFP angular distribution data for the 2+ (4.44 MeV) and 1+ (12.71 MeV) states are well described by the microscopic DWIA calculations.

Differential cross sections at θlab = 0.0°–12.3° and a complete set of polarization transfer observables at θlab = 0.0° are measured for the 90Zr(p, n) reaction at Tp = 295 MeV. A multipole decomposition (MD) technique is applied to the cross sections to extract partial cross sections σL with L=0, 1, 2, and 3 contributions. A significant amount of σL=0 is found in the highly excited continuum region. After subtracting the estimated iso-vector spin-monopole strength from σL=0, the Gamow-Teller (GT) strength B(GT) is deduced to be Sβ− = Σ B(GT) = 28 ± 1.6 ± 5.4. The total spin transfer Σ(0°) which is independent of the nuclear reaction mechanisms such as the effective nucleon-nucleon interaction or distortions is derived from the complete set of polarization transfer observables. It is close to unity up to 50 MeV excitation indicating the strong spin-flip character of the continuum. By using the relation between the polarization transfer observables the fractions of natural-parity and unnatural-parity transitions are also obtained and the dominance of unnatural-parity transitions in the continuum is found. These results are consistent with those derived from the MD analysis. The Sβ− − Sβ+ value is 27.1 and this is 90% of Ikeda's sum rule value of 3(N - Z)=30. Consequently it is concluded that the quenching of the GT strength is small and the quenching mechanism due to the ΔN− admixture seems to play a minor role.

We performed the measurement of magnetic properties of ferromagnetic steels that were degraded by tensile plastic deformation and cyclic loading, where lattice imperfections were produced in the steels. Magnetic hysteresis curves were changed depending on the load conditions. The changes in coercive force, residual magnetic flux density and permeability were obtained as functions of the magnitude of residual strain for the tensile tests and the number of loading cycles for the fatigue test. In the case of the tensile deformation, the coercive force increased and the residual magnetic flux density decreased with increasing the residual strains. In the case of fatigue damage accumulated by the cyclic loading, the residual magnetic flux density decreased with increasing the number of cyclic loading, while the coercive force remained constant. The changes in hysteresis curves were well consistent with the transmission electron microscopy (TEM) observation results of microstructural changes in the steels. We concluded that the magnetic property was enough sensitive to microstructural changes caused by mechanical deformation.

A detector system of the first focal plane of SMART, the 135 MeV/u high-resolution spectrometer at RIKEN Accelerator Research Facility, is described. It consists of a pair of multi-wire drift chambers and a trigger scintillator hodoscope contained in a He-filled detector box. A major subject using this system is the measurement of the (d, 2 He) reaction making the most of its large angular and momentum acceptances. Without seriously sacrificing the detection efficiency, reasonably good energy and angular resolutions for 2 He, 460 keV and 9 mrad (FWHM), respectively, have been achieved after optimizing the optics property of the spectrometer.

Polarized Raman spectra have been measured on single-crystal samples of monoclinic n-C36H74. Assignments of the Raman bands have been made on the basis of the observed polarization and on the temperature dependence of the spectra.