[en] As part of an NSF-JSPS Collaborative Research Project (JJ ampersand MF), giant resonances up to E_x ∼ MeV in ⁹⁰Nb have been studied with a 450-MeV ³He beam from the RCNP Ring Cyclotron. Tritons from (³He,t) were observed at 0=0 degrees with the K=1400 magnetic spectrometer Grand Raiden in coincidence with decay protons detected in eight SiLi detectors close to the target. Competition between γ, proton-, and neutron-emission affects the observed shape of the T=4 main Gamow-Teller resonance (GTR). The T=4 and T=5 GTR's and the spin-dipole resonance decay mostly to low-lying states in ⁸⁹Zr. Second-chance proton emission is also observed

[en] Microscopic structure of spin-isospin modes in ²⁰⁸ Bi has been studied in the reaction ²⁰⁸ Pb(³He, t)²⁰⁸ Bi at 450 MeV. Theoretical and experimental partial and total (escape) proton widths for the decay of IAR, GTR in ²⁰⁸ Bi into neutron-hole states in ²⁰⁷ Pb are obtained. 19 refs

No abstract available

No abstract available

[en] Spin observables have been measured for (p, 2p) reactions aiming at studying medium effects on NN interactions in nuclear field. Observed strong density-dependent reduction of the analyzing power is consistent with a model calculation where reduction of nucleon and meson masses are taken into account. The spin-transfer coefficients, which data are not reproduced by the model calculation, are found to be sensitive to reduction rate of each meson mass and have a possibility to test scaling lows in mass reductions. (author)

[en] A polarized deuterium target system was developed in order to measure the spin dependent cross sections of D vector (d vector, p)T nuclear fusion reaction at 20 MeV. By considering the nuclear fusion experiment in the low energy region, the deuterated polyethylene foils of 30-50 μm thicknesses were employed as a polarized target for the easy treatment to form as thin foil. The polarized deuterium target system consists of mainly a ³He-⁴He dilution cryostat, a 2.5 T superconducting magnet, a 70 GHz μ-wave system for the dynamical nuclear polarization method and a NMR system monitoring the target polarization. This polarized target was set in the 1st experimental hall of University Tsukuba Tandem Accelerator Center (UTTAC). The target polarization was determined by comparing the enhanced NMR signal with the target asymmetry measurement of D vector(d, d)D elastic scattering by 20 MeV deuteron beam. (author)

[en] Spin-isospin states in ¹³N have been studied by means of the ¹³C (³He,t) reaction at and near zero degree, at E(³He)=450 MeV. Decayed γ-rays from each state were measured at backward angle in coincidence with the ejectile tritons. The branching ratio of γ decay for some of spin-isospin states were determined and were compared to those from previous data. (author)

[en] Initial experiments were carried out to study spin-isospin transitions in nuclei using (t,³He) measurements. A triton beam was produced from the breakup reaction (⁴He,t-p) on a 9.25 g/cm² Be production target using a ⁴He beam of 620 MeV. With a beam of 70 enA a yield of 381 MeV tritons with 4.5 x 10⁶ particles/s was achieved. The first half of the A1200 beam transport system at NSCL was used to analyze the triton beam. The energy spread at the target position was estimated to be about 23 MeV. The second half of the A1200 was used to analyze the energy of ³He particles from the (t,³He) reaction. The dispersion matching method was applied to obtain good energy resolution despite the significant energy spread of the incident tritons. The achromatic properties of the A1200 system made it possible to obtain high-resolution (t,³He) spectra at θ=0 with a resolution of ΔE/E=0.002 (ΔE=780 keV). (orig.)

[en] The performance of scintillating fiber detectors with 2 m long light guides was investigated for COMPASS experiment, using a 450 MeV/c electron beam.Prototypes consisting of 0.5 mm diameter fibers (Kuraray SCSF-38 single-cladding) with the position-sensitive photomultipliers H6568 (Hamamatsu) were constructed for the test. The time resolution of σ∼430 ps was obtained with about 10 photoelectrons for the prototype of 10-layers structure. (author)

[en] A prototype gamma ray detector for the detection of π⁰ in the proposed experiment at SPring-8 to study the Gerasimov-Drell-Hearn (GDH) sum rule (GDH experiment) has been built and tested. The detector is fabricated with lead-scintillator tiles and wave length shifter fiber readout. This detector will be placed inside the bore of the superconducting magnet which supplies the polarized target with a 2.5 T magnetic field. High-detection efficiency (above 85%) for the gamma rays is the most important requirement for this detector to be employed in the proposed experiment. It has been tested with minimum ionizing particles, electrons and gamma rays. The results of the tests in comparison with some Monte Carlo simulations are presented. The evaluated efficiency for gamma rays ranging in energy above 50 MeV is higher than 90%