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Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the α resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of 7Be+α resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the 7Be(α, ã ) reaction, and proposed a new cluster band in 11C. [ABSTRACT FROM AUTHOR]

The cluster structures of the excited states in 11B and 13C were discussed by measuring the isoscalar monopole strengths in the inelastic α scattering at Eα = 388 MeV. It was found that the 1/22-, 1/23-, and 1/24- states in 13C are candidates for the α cluster states with a 3α+n molecular configuration. [ABSTRACT FROM AUTHOR]

Measurements of analyzing powers Ay, Ayy, and Axx for d-p elastic scattering were performed at Ed = 0.88 and 2.0 GeV using a high-energy deuteron beam polarimeter at the Internal Target Station of the Nuclotron at JINR. The analyzing power data at 0.88 GeV are compared with several theoretical calculations. [ABSTRACT FROM AUTHOR]

From the recent studies, it has been found that the differential cross sections of the elastic Nd scattering at the energy below 150 MeV can be well reproduced by incorporating the 3NF in the Faddeev calculation based on modern nucleon-nucleon (NN) interactions. On the other hand, the differential cross sections of nd and pd at 250 MeV show large discrepancies between the data and the Faddeev calculations with 3NF. It indicates the presence of the missing features of the three nucleon system at this energy region. For the next step of the 3NF study, we measured the vector analyzing power Ay and the differential cross sections for the 2H(p, pp)n breakup reaction at 250 MeV. The experiment was carried out by detecting two protons in the final state with using the double-armed spectrometer Grand Raiden (GR) and Large Acceptance Spectrometer (LAS) at Research Center for Nuclear Physics (RCNP). These data provide important information on the 3NF effects and make a discrimination between 3NF models. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Experimental technique for measuring proton inelastic scattering with high-resolution at 295 MeV and at forward angles including zero degrees is described. The method is useful for extracting spin part of the M1 strength via nuclear excitation as well as E1 strength via Coulomb excitation. An excitation energy resolution of 20 keV, good scattering angle resolution, and low background condition have been achieved. The experimental technique was applied for several sd and pf shell nuclei. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new type of the spin polarized solid proton target has been constructed which can be operated under a low magnetic field of 0.08 T and a high temperature of 100 K. First polarization asymmetry measurement with an unstable beam of 6He with an energy of 71 MeV/u has been successfully carried out. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The cross sections and analyzing powers of the 16O(p,p′)16O(0-,T = 1) scattering were measured at a bombarding energy of 295 MeV and an angular range of 14° ≤ θlab ≤ 30°. The isovector 0- state at Ex = 12.80 MeV is clearly separated from the neighboring states with an energy resolution of ΔE ≃ 30 keV. The data have been compared with distorted wave impulse approximation (DWIA) calculations. The analyzing powers are sensitve to the effective nucleon-nucleon (NN) interaction used in DWIA calculations, and our data support the medium modification of the NN interaction in nuclei. The DWIA calculation employing a random phase approximation (RPA) response function predicts an enhancement of the cross sections around a momentum transfer of q ≃ 1.7 fm-1, and it gives a reasonable agreement with the data. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

The isoscalar giant dipole resonance (ISGDR) has been investigated in [sup 208]Pb using inelastic scattering of 400 MeV α particles at extremely forward angles, including 0°. Using the superior capabilities of the Grand Raiden spectrometer, it has been possible to obtain inelastic spectra devoid of any “instrumental” background. The ISGDR strength distribution has been extracted from a multipole-decomposition of the observed spectra. The implications of these results on the experimental value of nuclear incompressibility are discussed. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Complete sets of observables in proton inelastic scattering from [sup 16]O have been measured at forward angles including 0°. Obtained spectra were decomposed into spin-flip and non spin-flip spectra by polarization transfer coefficients and spindipole strength spliting into several peaks was identified in the giant resonance region of E[sub x] = 19 ∼ 27 MeV in [sup 16]O. [ABSTRACT FROM AUTHOR]

Polarization transfer (PT) coefficients in the [sup 12]C, [sup 28]Si(p,p') reactions at a scattering angle of 0° are measured at E[sub p] = 392 MeV. The strength of the isoscalar central spin-dependent part (V[sub σ]) of the effective nucleon-nucleon interaction is studied by using the sensitivity of the PT coefficients for the excitation of the 1[sup +], T=0 state in [sup 12]C to the V[sub σ] strength. It is found that distorted wave impulse approximation (DWIA) calculations employing the Francy and Love effective interaction well reproduce the measured PT coefficients. [ABSTRACT FROM AUTHOR]

We have constructed an experimental ensemble to measure polarization transfer observables in proton inelastic scattering at zero degrees. Excited states can simultaneously be measured for the excitation energy from 5 MeV to 35 MeV at E[sub p]=400 MeV. A fast data acquisition system has been developed to endure the large background event rate originated by the primary beam itself. We have found the effective analyzing power of the focal plane polarimeter slightly depends on the treatment of two-ray events. [ABSTRACT FROM AUTHOR]

Abstract. We present a new measurement of the energy dependence of nuclear transparency from AGS experiment E850, performed using the EVA solenoidal spectrometer, upgraded since 1995. Using a secondary beam from the AGS accelerator, we simultaneously measured pp elastic scattering from hydrogen and (p, 2p) quasi-elastic scattering in carbon at incoming momenta of 5.9, 8.0, 9.0, 11.7 and 14.4 GeV/c. This incident momentum range corresponds to a Q² region between 4.8 and 12.7 (GeV/c)². The detector allowed us to do a complete kinematic analysis for the center-of-mass polar angles in the range 85° - 90°. We report on the measured variation of the nuclear transparency with energy and compare the new results with previous measurements. [ABSTRACT FROM AUTHOR]

Abstract. We present an analysis of new data from Experiment E850 at BNL. We have characterized the inclusive cross section near the endpoint for pp cxclusive scattering in Hydrogen and in Carbon with incident beam energy of 6 GeV. We select events with a pair of back-to-back hadrons at large transverse momentum. These cross sections are parameterized with a form ... ~ (1 - X[sub L])[sup p], where X[sub L] is the ratio of the longitudinal momentum of the observed pair to the total incident beam momentum. Small value of p may suggest that the number of partons participating in the reaction is large and reaction has a strong dependence on the center-of-mass energy. We also discuss nuclear effects observed in our kinematic region. [ABSTRACT FROM AUTHOR]