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A cross section measurement employing a direct O detection method for the reaction energies from E = 2.4 to 0.7 MeV is planned at Kyushu University Tandem Laboratory. To perform this experiment and to obtain quantitative information about the cross section to within an error of 10%, we have developed several instruments, including a blow-in type windowless gas target and a ionization chamber. A target thickness of 24 × 3.9 Torr cm was achieved using the developed gas target. The particle identification was successfully performed by using the energy deposit in the ionization chamber. Experiments were performed at E = 2.4 and 1.5 MeV using the developed instruments and the cross sections were obtained. [ABSTRACT FROM AUTHOR]

Space Star (SS) anomalies in nd and pd breakup reactions below 20 MeV were reported since 1989, but their origin has not been found yet. We have considered two conditions for the SS anomalies : condition (a) where three outgoing nucleons form an equilateral triangle and condition (b) in which the triangle is perpendicular to the beam axis. The condition (b) was investigated by our previous systematic experiments on pd breakup. In the present study, we started systematic experiments for the condition (a). [ABSTRACT FROM AUTHOR]

Cross sections of pd breakup reaction at E = 250 MeV were measured systematically in single-proton detection and in two-proton coincidence detection. Measured cross section is up to two times higher than calculated ones. The enhancement of breakup cross section is similar to reported enhancement in pd elastic scattering cross section. Origins of this enhancement are discussed. [ABSTRACT FROM AUTHOR]

Space Star anomaly in Nd breakup reaction below 20 MeV is well-known. Also, Quasi-Free Scattering (QFS) anomaly in Nd breakup reaction below 40 MeV has been reported from several experiments. Origin(s) of QFS anomaly has not been known, similarly to origin(s) of SS anomaly. We have been making a systematic measurement on pp-QFS cross section, previously at E = 9.5 MeV and 13 MeV and recently at 7.5 and 19 MeV. We used an unpolarized p-beam to correctly measure only cross section. Our data agreed well with pd calculation by A. Deltuva. So far, no pp-QFS anomaly has been found in our experiments. [ABSTRACT FROM AUTHOR]

C+He fusion reaction at E = 0.3 MeV is one of the main reaction in He-burning in stars, and is very important in nuclear synthesis. However the fusion cross section has not been determined yet in spite of 40 years efforts in the world. Recently we succeeded in the measurement at 1.5 MeV. We have a plan to make direct measurement of the total fusion cross section down to 0.7 MeV at Kyushu University Tandem accelerator Laboratory (KUTL), and to determine the cross section at 0.3 MeV by extrapolation. [ABSTRACT FROM AUTHOR]

Inclusive measurements of the D( p, p) pn reaction were made at incident proton energies of 248 MeV and 13 MeV, to investigate the global feature of the pd breakup reaction at intermediate and low energies. At 248 MeV, the cross section and analyzing power A y were measured at four angles from 7° to 20°. The data largely disagree with Faddeev calculations even if 2π-exchange three-nucleon force (2π3NF) or Δ-isobar is included, and the disagreement increases at forward angles. At 13 MeV, the cross section was measured at eight angles from 10° to 70°. The data are well reproduced by a recent pd Faddeev calculation, and the effects of Δ-isobar at 13 MeV are very small. [ABSTRACT FROM AUTHOR]

A measurement of tensor analyzing power and of reaction at was made at RCNP. Both the relation of and the discrepancy in between experiment and calculations were confirmed at 137 MeV, in consistent with our previous measurement at 196 MeV. Present data are compared with KVI data at 133 MeV. [Copyright &y& Elsevier]

We made three kinds of measurements at ; i) experiment at ppFSI, ii) experiment at , and iii) experiment at many angle pairs around the space star. For an easy estimate of Coulomb effects in pd breakup reaction, we proposed Watson- Migdal & Faddeev calculation which was found to give nearly the same results as the pd calculation by Deltuva et al.. Cross sections of i) and ii) are well reproduced by the pd calculation, however, 10-15% discrepancy has been found between the cross section of iii) and the calculation. [Copyright &y& Elsevier]

We have measured angular distributions of the differential cross-section, the analyzing power and all of the spin transfer coefficients Ky1y,Kx1x, Kz1x and Kz1z for the pd elastic scattering at 250 MeV. These are the first measurements of a complete set of proton polarization observables for pd elastic scattering at intermediate energies. The present data are compared with theoretical predictions based on exact solutions of the three-nucleon Faddeev equations and modern realistic nucleon-nucleon potentials combined with three-nucleon forces (3NF), namely the Tucson-Melbourne (TM) 2π-exchange model, a modification thereof (TM') closer to chiral symmetry, and the Urbana IX model. [ABSTRACT FROM AUTHOR]

In our previous inclusive experiment on H( p, p) pn at 247 MeV, the measured cross section at forward angles is about twice larger than 3 N calculation with ππ 3NF. Therefore, we have made an exclusive experiment on H( p, p p) n at the same energy. The preliminary data suggest that the cross section was enhanced at forward angle of θ and θ. [ABSTRACT FROM AUTHOR]

In our previous measurement of pd radiative capture at E d = 137 and 196 MeV, we found an interesting fact that the measured tensor analyzing powers show the relation A xx ≈ A yy , although calculated A xx and A yy are apparently different, A xx ≠ A yy . The measured A yy agrees fairly well with the 3 N calculations, and the measured A xx largely disagrees with calculated A xx . Similar experiments on pd capture have been made at KVI at nearly the same energies of 130–180 MeV. The KVI data also support A xx ≈ A yy relation, but absolute values of A xx and A yy at KVI are about half of RCNP data. Therefore, we made a new experiment of pd capture at E d = 196 MeV. A zz was measured in three different ways, and data analysis is in progress. Preliminary data seem to support our previous data. [ABSTRACT FROM AUTHOR]