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We report measurements of cross sections and analyzing powers for nucleon-knockout $(\stackrel{P\vec}{p},np)$ reactions of $^{2}\mathrm{H}, ^{6}\mathrm{Li}$, and $^{12}\mathrm{C}$ at 296 MeV using the RCNP NPOL3 neutron detector and large acceptance spectrometer. The $1s$ and $1p$ knockout reactions were successfully separated with a separation-energy resolution of approximately 6 MeV. The resulting data were compared with plane-wave and distorted-wave impulse approximation calculations employing the nucleon-nucleon $t$ matrix in free space. No significant differences were identified in the case of the present analyzing power data, in contrast to the significant reductions observed in $(\stackrel{P\vec}{p},2p)$ values. The conventional Pauli blocking and nuclear binding effects with the $g$ matrix and the relativistic effect of nucleon mass reduction in the nuclei are also discussed.

We have developed the neutron polarization measurement system to perform the first polarization-transfer measurement for the exclusive [Formula: see text] reaction. For the neutron polarization measurement, we have reconstructed the neutron polarimeter NPOL3. The NPOL3 system has been calibrated by using the polarized neutron from the [Formula: see text] reaction, and the resulting effective analyzing power is [Formula: see text]. For the exclusive measurement, the Large Acceptance Spectrometer (LAS) has been used for the recoil proton detection. The energy resolution of 6 MeV is achieved for separation energy, which is sufficient to separate the [Formula: see text] and [Formula: see text] orbits for light nuclei.

We present measurements of the cross section and a complete set of polarization observables for the Gamow‐Teller 12C(p,n)12N(g.s.;1+) reaction at an incident proton energy of 296 MeV. The complete set of polarization observables is used to separate the cross section into spin‐longitudinal and spin‐transverse components. From the comparison with the distorted wave impulse approximation calculations employing random phase approximation response functions, we found that our data showed the existence of the pionic and rho‐mesonic correlations in nuclei.

The double differential cross sections for the 116Cd(p,n) and 116Sn(n,p) reactions at 300 MeV have been measured over a wide excitation‐energy region including Gamow‐Teller (GT) giant resonance (GTGR) for studying GT transition strengths in the intermediate nucleus of the 116Cd double‐β decay, namely 116In. A large amount of the strengths in the β+ direction has been newly found in the energy region up to 30 MeV, which may imply that the GT strengths in the GTGR region contribute to the nuclear matrix element of the two‐neutrino double‐β decay.

Recently it was found that the differential cross sections of elastic Nd scattering below 150 MeV can be well reproduced by incorporating a 3NF in Faddeev calculations based on modern nucleon‐nucleon (NN) interactions. On the other hand, the differential cross sections for nd and pd at 250 MeV show large discrepancies between the data and the Faddeev calculations with a 3NF. This indicates the existence of the missing features of the three nucleon force in this energy region. For the next step in the 3NF study, we have 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 the Large Acceptance Spectrometer (LAS) at the Research Center for Nuclear Physics (RCNP). The data was compared with the results of Faddeev calculations with and without a 3NF.