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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.

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.

The cross sections and analyzing powers were measured for 3He+12C, 58Ni, and 90Zr elastic scattering at T3He=450 MeV. The incident energy dependence of the volume integral per nucleon for 3He shows the similar behavior to that of protons if the spin‐orbit potential is taken into account. This result supports the assumption that interactions between 3He and nucleus are dominated by the interactions between constituent nucleons of 3He and target nucleus in the intermediate energy region. The results of the single folding calculation suggest the interaction between point nucleon and target nucleus is modified in the 3He+nucleus elastic scattering.

Cross sections and polarization transfer observables in the 16O(p,p′) reactions at 392 MeV were measured at forward angles including 0°. The non‐spin‐flip (ΔS = 0) and spin‐flip (ΔS = 1) strengths in transitions to several discrete states and broad resonances in 16O were extracted using a model‐independent method. The giant resonances in the energy region of E x = 19–27 MeV were found to be predominantly excited by ΔL = 1 transitions. The strength distribution of spin‐dipole transitions with ΔS = 1 and ΔL = 1 were deduced. The obtained distribution was compared with a recent shell model calculation. Experimental results are reasonably explained by distorted‐wave impulse‐approximation calculations with the shell model wave functions.

The isoscalar giant dipole resonance (ISGDR) has been investigated in 208Pb using inelastic scattering of 400 MeV alpha particles at forward angles, including 0deg. Using the superior capabilities of the Grand Raiden spectrometer, it has been possible to obtain spectra devoid of any "instrumental" background. The ISGDR strength distribution has been extracted from a multipole-composition of the observed spectra. The implication of these results on the experimental value of nuclear incompressibility are discussed., Comment: 5 pages total. 3 figures. Invited talk at INPC2001,Berkeley, July 30-Aug. 3, 2001

We have designed and constructed a new beam line which can accomplish both lateral and angular dispersion matching with the Grand Raiden spectrometer. In dispersive mode, lateral and angular dispersions of the beam line are b16=37.1 m and b26=−20.0 rad, respectively, to satisfy matching conditions for Grand Raiden. In achromatic mode, the beam line satisfies the double achromatic condition of b16=b26=0. The magnifications of the beam line are (Mx ,M y) = (−0.98, 0.89) and (−1.00, −0.99) for dispersive and achromatic modes, respectively. In the commissioning experiments, we have succeeded to separate the first excited 2 + state of 168 Er with Ex=79.8 keV clearly from the ground state in the (p, p � ) reaction. We achieved energy resolutions of ∆E=13.0±0.3 keV and 16.7±0.3 keV in full width at half maximum for 295 MeV and 392 MeV protons, respectively. These energy resolutions agree with the resolving power of Grand Raiden for an object size of about 1 mm.

Elastic scattering of 65 MeV polarized protons from Sm isotopes, $^{164}\mathrm{Dy}$, and $^{172}\mathrm{Yb}$ has been measured. The volume integrals of the real central part and the spin-orbit part of the optical potential show anomalously low values for deformed nuclei. The origins of these anomalies are discussed.NUCLEAR REACTIONS $^{144}\mathrm{Sm}$, $^{148}\mathrm{Sm}$, $^{150}\mathrm{Sm}$, $^{152}\mathrm{Sm}$, $^{154}\mathrm{Sm}$, $^{164}\mathrm{Dy}$, $^{172}\mathrm{Yb}$(p,p), $^{164}\mathrm{Dy}$(p,p\ensuremath{'}), $E=65$ MeV; measured $\ensuremath{\sigma}(\ensuremath{\theta})$, $A(\ensuremath{\theta})$; deduced optical-model parameters, coupled channel parameters, volume integrals for the real central potential, volume integrals for the real spin-orbit potential.

Elastic scattering of polarized protons from sd and fp shell nuclei has been studied with high-purity germanium detectors. The mean square radius of the central real part of the fitted optical potential was found to be of the form a + bA 2 3 . Comparison with the radius from electron scattering gives the range of the effective two-body interaction and its A dependence as 〈 r 2 〉 d =(4.5±0.4)+(0.16±0.03) A 2 3 fm 2 .