Narrow Results

We have investigated the prototype of -nuclear systems, ppK⁻, with a realistic NN potential and effective local potentials based on chiral SU(3) dynamics. Including estimates of theoretical uncertainties, we find that ppK⁻ is not deeply bound, with a total binding energy = 19 ± 3 MeV and mesonic decay width between about 40 and 70 MeV. The component in the ppK⁻ compound is of a similar structure as the two-body quasibound state embedded in the πΣ continuum.

³He + p scattering phase shifts for the S- and P-waves are studied in a microscopic cluster model in order to investigate the role of the d + 2p channel in the low-energy phase shifts. In the present cluster model, the description of the ³He wave function is extended from a simple (0s)³ model to a three-body model and two different nucleon-nucleon interactions, the Minnesota and AV8' potentials, are employed. The present extended cluster model shows that the d + 2p channel is indispensable to reproduce the resonant phase shifts in the AV8' potential while it plays a minor role in the MN potential. On the contrary, the role of this channel in the S-wave non-resonant phase shifts is negligible in both potentials.

Considering the mixing of scalar mesons, the ΩΩ and Ξ*Ω systems are dynamically investigated within the framework of the chiral SU(3) quark model by solving the resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a good description of the energies of the baryon ground states, the binding energy of deuteron, and the experimental data of the nucleon–nucleon (NN) and nucleon–hyperon (NY) scattering processes. Two different mixing cases, one is the ideal mixing and another is 19° mixing, are discussed. The results show that no matter what kind of mixing is adopted, the ΩΩ and Ξ*Ω systems are still bound states. It is also shown that they are deeply bound if 19° mixing is adopted.

The deuteron-proton elastic scattering is considered at the deuteron energies from 500 up to 2000 MeV. The multiple-scattering-expansion technique is applied to evaluate the reaction amplitude. The one-nucleon-exchange, single scattering and double scattering contributions are taken into account. Also, some relativistic effects are included into consideration. The obtained results are compared with the experimental data both for the differential cross section and polarization observables.

The mixing of scalar mesons is introduced into the baryon-baryon system in the chiral SU(3) quark model to further dynamically investigate the Di-omega state by using the same parameters as those in reasonably describing the experimental hyperon-nucleon and nucleon-nucleon scattering data. Two different mixings of scalar mesons, the ideal mixing and 19° mixing, are discussed, and compared with no mixing. The results show that it is still deeply bound state if 19° mixing is adopted, the same as those of no mixing. However, for ideal mixing, the binding energy is reduced quite a lot, yet it is still a bound state.

In light of a new experiment which claims an identification of tetraneutron, we discuss the results of experimental search of trineutron and tetraneutron in different nuclear reactions. A summary of theoretical studies for trineutron and tetraneutron within variety of approaches are presented.

In the study of K^-pp that is the most essential -nuclear system, the coupling dynamics of and πΣN is important. In case that the K^-pp is considered as a coupled channel system, we need to treat it as a resonant state, because the πΣN channel is an open channel. We propose the application of the Complex Scaling Method (CSM), which is a powerful tool for the treatment of resonant states, to the study of K^-pp. In this article, we report the result of our test calculation for the two-body case, system corresponding to Λ(1405) studied with a phenomenological potential.