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We present a precise measurement of the cross section, proton and $\rm ^3He$ analyzing powers, and spin correlation coefficient $C_{y,y}$ for $p$-$\rm ^3He$ elastic scattering near 65 MeV, and a comparison with rigorous four-nucleon scattering calculations based on realistic nuclear potentials and a model with $\Delta$-isobar excitation. Clear discrepancies are seen in some of the measured observables in the regime around the cross section minimum. Theoretical predictions using scaling relations between the calculated cross section and the $\rm ^3 He$ binding energy are not successful in reproducing the data. Large sensitivity to the $NN$ potentials and rather small $\Delta$-isobar effects in the calculated cross section are noticed as different features from those in the deuteron-proton elastic scattering. The results obtained above indicate that $p$-$\rm ^3He$ scattering at intermediate energies is an excellent tool to explore nuclear interactions not accessible by three-nucleon scattering., Comment: 22 pages, 6 figures

We performed the experiment of p–^{3}3He scattering at 65 MeV by using polarized proton beams and the newly constructed polarized ^{3}3He target. The proton analyzing power A_{y}Ay, the ^{3}3He analyzing power A_{y}^{T}AyT, and the spin correlation coefficient C_{yy}Cyy were measured. In the conference, the experimental data were compared with the rigorous numerical calculations based on various nuclear potentials. Large discrepancies between the experimental data and the calculations were found in the A_{y}^{T}AyT and the {C_{yy}}Cyy at the backward angles.

We performed the measurement of the cross section and the proton analyzing power \(A_y\) for p–\(^3\)He elastic scattering with a 65 MeV polarized proton beam at Research Center for Nuclear Physics (RCNP), Osaka University. The proton analyzing power \(A_y\) data are compared with the theoretical calculations based on the nucleon–nucleon potential (INOY04).

The \(^3\)He analyzing powers for \(p{-}^3\)He elastic scattering with the polarized \(^3\)He target have been measured at \(70~\mathrm {MeV}\). \(^3\)He polarization which was calibrated by the electron paramagnetic resonance method was achieved to \(50\%\). In the conference the data were compared with the theoretical calculations based on the modern nucleon–nucleon potentials. Large discrepancies between the theoretical calculations and the experimental data were found at the angles where the \(^3\)He analyzing power takes minimum and maximum.

International audience; Differential cross sections of p–6He elastic scattering were measured in inverse kinematics at an incident energy of 200 A MeV, covering the high momentum transfer region of 1.7–2.7 fm−1. The sensitivity of the elastic scattering at low and high momentum transfers to the density distribution was investigated quantitatively using relativistic impulse approximation calculations. In the high momentum transfer region, where the present data were taken, the differential cross section has an order of magnitude higher sensitivity to the inner part of the 6He density relative to the peripheral part (15:1). This feature makes the obtained data valuable for the deduction of the inner part of the 6He density. The data were compared to a set of calculations assuming different proton and neutron density profiles of 6He. The data are well reproduced by the calculation assuming almost the same profiles of proton and neutron densities around the center of 6He, and a proton profile reproducing the known point-proton radius of 1.94 fm. This finding is consistent with the assumption that the 6He nucleus consists of a rigid α-like core with a two-neutron halo.

The National Institutes for Quantum and Radiological Science and Technology (QST) manages various types of ion sources for research and development in the fields of life sciences, medical and industrial applications, and fusion energy science. The QST is currently developing on electron cyclotron resonance ion sources, negative ion sources (ion sources for fusion and for tandem accelerators), ion sources for radioactive beams, laser ion sources, and miscellaneous ion sources. Its intra- and inter-institutional collaborations make QST a promising platform for future ion source technologies.

Radio-isotope (RI) beam experiments have extended the horizon of nuclear physics to nuclei far from the stability line. Nuclear reactions such as (p,p), (p,d), (p,pp), (p,pn) etc. with spin degrees of freedom are expected to provide rich information on nuclear structure of unstable nuclei. However, the RI beam experiment utilizes the inverse kinematics and therefore it involves detection of low energy proton or deuteron which is emitted to angles nearly 90° in the lab. system. A conventional polarized proton target system is inconvenient for such experiments since it requires a high magnetic field (≥ 2.5T) as well as a very low temperature (≤ 1K). We are developing a new spin polarized solid proton target (SPSPT) system [1] which can be operated in a low magnetic field (~ 0.3T) at a high temperature (77K).