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The structures of Ωω states with spin-parity Jp = 5/2−, 3/2−, and 1/2− are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground states, the binding energy of the deuteron, the nucleon-nucleon (NN) scattering phase shifts, and the hyperon-nucleon (YN) cross sections. The calculated results show that the Ωω state has an attractive interaction, and in the extended chiral SU(3) quark model such attraction can make for a Ωω quasi-bound state with spin-parity Jp = 3/2− or 5/2− and the binding energy of about several MeV.

Previously, we extended our chiral SU(3) quark model to include the coupling between the quark and vector chiral fields [Nucl. Phys. A 727 (2003) 321]. Here we further study the structure of (ΩΩ)ST = 00 dibaryon in the extended chiral SU(3) quark model by solving a resonating group method equation. The vector meson exchanges effect, hidden colour channel and colour screening effect are investigated, respectively. The results show that the (ΩΩ)ST = 00 system is still the deeply bound state in the extended chiral SU(3) quark model in which the vector meson exchanges control the short-range quark–quark interaction, which is similar to the results obtained from the chiral SU(3) quark model. When the model space is enlarged by including the hidden colour channel, it is found that the energy of the hidden colour state |CCstr = −6,ST = 00 is much higher than that of the (ΩΩ)ST = 00 state, thus the CC channel has little effect on the binding energy of (ΩΩ)ST = 00 state. When the error function confinement potential is considered, the bound state property would not change largely. Further, scalar meson mixing is considered. No matter whether θS = −18° or ideal mixing is taken, (ΩΩ)ST = 00 state is still a bound state.

The low-energy region kaon-pion S- and P-wave phase shifts with isospin I = 1/2 and I = 3/2 are dynamically studied in the chiral SU(3) quark model by solving a resonating group method equation. The model parameters are taken to be the values fitted by the energies of the baryon ground states and the kaon-nucleon elastic scattering phase shifts of different partial waves. As a preliminary study the s-channel q(-q) annihilation interactions are not included since they only act in the very short range and are subsequently assumed to be unimportant in the low-energy domain. The numerical results are in qualitative agreement with the experimental data.

The structures of (ΩΩ)0+ and (([1])Ω)1+ are studied in the extended chiral SU(3) quark model in whichvector meson exchanges are included. The effect from the vector meson fields is very similar to that from the one-gluonexchange (OGE) interaction. Both in the chiral SU(3) quark model and in the extended chiral SU(3) quark model,di-omega (ΩΩ)0+ is always deeply bound, with over one hundred MeV binding energy, and (([1])Ω)1+ 's binding energyis around 20 MeV. An analysis shows that the quark exchange effect plays a very important role for making di-omega(ΩΩ)0+ deeply bound.

The chiral SU(3) quark model is extended by including the vector meson exchanges to describe the short range interactions. The phase shifts of NN scattering are studied in this model. Compared with the results of the chiral SU(3) quark model in which only the pseudo-scalar and scalar chiral fields are considered, the phase shifts of 1S0 wave are obviously improved.

The cross sections of Ω + Ξ → (ΩΩ)Jπ=0+ + K(K*) and Ω + Ω → (ΩΩ)Jπ=0+ + η'() are studied by using an effective Hamiltonian method. For the two pseudo-scalar meson production processes, the cross sections are still in the order of several μbs, but for the two vector meson production processes, the cross sections are about 10 times larger than those in pseudo-scalar meson production case when the coupling constants of vector meson fields are fixed according to gNNρ and fNNρ in NN scattering and the SU(3) relation.

The cross sections of Ω + Ω→ (ΩΩ)Jx+ X are studied by using an effective Hamiltonian method.The results are ern+ΩΩ→(nΩ)0++ = 0.03 ～ 0.16 × 10- cm2 for pn = 100 ~ 400 MeV,and the cross sections ofη production are about 10-28 cm2 for pΩ＞ 880 MeV.

The structure of a new dibaryon (ΩΩ)0+ is studied and predicted in the framework of the chiral SU(3) quark model by solving a resonating group method equation. The binding energy of this dibaryon is around 100 MeV, the mean root square of the distance between two Ωs is 0.84 fm and the preliminary estimated mean lifetime is about two times longer than that of the free Ω. All these interesting properties and also the two negative charge units it carried could make it be easily identified experimentally in the heavy-ion collision process. The production probability of this new dibaryon in 158A GeV Pb+Pb collision is estimated using the thermal model, which is of the order of 10-6 to 10-5 per event; And it is expected, that with the increase of temperature, the production rate will also be increased.

We discuss the structure of deltaron dibaryon in the chiral quark model. The energy of deltaron is obtained by considering the coupling of the and CC (hidden color) channels. It is shown that the mass of deltaron is lower than the mass of but higher than the mass of .

By using the color confinement potential which includes the color screening effect, we studied the baryon spectra and the nucleon-nucleon interaction. The results show that the color screening effect not only improves the baryon spectrum calculation, but also can solve the long-tail problem of the color Van der Waals force. A part of the medium attraction of the nuclear force can be obtained from the color Van der Waals force.

The leptonic decay of charmonium is studied by using an error function confinement potential in which the color-screening effect is considered. The relativistic correction of the quark-antiquark potential is also included in the calculation. The discrepancy means that there should be some other effects in explaining charmonium high-lying states.

In this paper, we have derived a nonrelativistic transition potential V q-qq q from one-gluon-exchange theory and calculated the matrix elements of the nucleon-meson vertices and isobar-meson vertices from this transition potential by using the generator coordinate method. The coupling constants of the vertices are in agreement with the experimental data and the form factors of the vertices are much like gaussian functions.

Nucleon-nucleon interaction is studied in the non-relativistic quark model with a flat bottom linear confinement potential. The results are consistent with the calculated ones from the lattice quantum chromodynamics. The quark-quark interaction also consists of those caused by the one gluon exchange and the one pion exchange. The phenomenological sigma meson exchange between two nucleons is also included to fit the S-wave N-N scattering data. The calculated NN channel S-wave phase shifts show that the flat bottom linear confinement potential can provide part of the medium range attraction.

The equivalent one-boson-exchange potentials of the N-N, N-Δ and Δ-Δ interaction were calculated rigorously in momentum space with the vertex functions derived from quark-pair-creation model. The results of the N-N interaction were compared with those calculated approximately in coordinate space and the conventional one-boson-exchange potentials. All of the results indicate that they have very similar behaviour for the medium- and Long-range parts.

All the effects including bound neutron wavefunction, short range correlation and proton distortion on the angular distribution of 3He(P,π+)4He have been studied. A rather good result has been achieved.

The procedure of the derivation of one gluon exchange quark-quark potential is extended from the case of on shell to that of off shell. A phenomenological transition potential between valence quark and sea quark is obtained.

The purpose of this paper is to study the Λ-N interaction by using the meson exchange theory. We have considered four processes:l) Single K meson exchange, 2) Single η and single ω meson exchange, 3) Box diagrams of 2π and πρ exchanges with the intermediate states of ΣN, and 4) Box diagrams of 2π and πρ exchanges with the intermediate states of ΣΔ. For simplicity, the zero initial momentum approximation and the closure approximation have been taken in the calculation. The results are reasonable and consistent with experimental data. Especially for the cases of and , the theoretica1 spectra of and are in good agreement with experimental data.

A comparatively detailed nonrelativistic investigation of the (p, π+) reaction has been made using Single-Nucleon-Mechanism. The results show that if eikonal distortion is a good approximation to high and medium energy scattering, SNM is inadequate to describe the reaction in producing asymmetry.

We have calculated the cross section and the S wave phase shift of the Λ-P elastic scattering by using the meson exchange potential which is obtained in Ref.[1]. The results are in good agreement with agreement with the experimental data.

Decay rate of ρ-meson into two π-mesons was calculated by using the transition potential of a quark-antiquark pair creation model. The theoretical result is in good agreement with the experimental data. Also, the difference of decay widths for processes ρ±→π±π0 and ρ0→π+π- was discussed.

The energy spectrum and production probabilities of the ground state and the excited states of Λ 13 C are calculated by using the SU 3 ⊗SU 2 supermultiplet classification method given in a previous paper. The calculated results show that the experimental peak at about 11 MeV is almost the same as the supersymmetric state not only in energy position but also in production rate. It may be evidence for the existence of the supersymmetric state in hypernuclei, which is a new mode of excitation that is forbidden to occur in nuclei.

The N-N interaction is studied in the framework of non-relativistic quark model using the resonating group method (RGM). The ΔΔ channel is taken into account in addition to the NN channel. The calculated S-wave phase shifts show that the channel coupling effect is increased if the quadratic or the linear confinement is replaced by the flat-bottom-linear confinement. This result is quite different from that in the case of the quadratic confinement or the linear confinement, in which this channel coupling effect is negligible.

Baryon–meson vertex structure of the system including s quark was studied from one–gluon–exchange quark-antiquark pair creation model. The theoretical coupling constants are in good agreement with the experimental data except for the cases including meson, in which the theoretical results are not large enough in comparison with the measured values.

In this paper, a Λ–N potential is presented. The long and medium range parts of this potential are given by the OBEP and TBEP , while the short range part by a phenomenological soft core. Based on the Λ–N potential, the Λ–separation energies and the spectra of and as well as the s-wave phase shifts and the cross section of the Λ–N elastic scattering are calculated. The results are in good agreement: with the experimental data. Finally, the Λ–well depth in nuclear matter is discussed.

In this paper the matrix elements of the nucleon-meson vertexes from one gluon exchange transition potential are calculated by using the generator coordinate method. We have found that the coupling constants of the nucleon-meson vertexes are roughly in agreement with the experimental data and the form factors of the vertexes are quite like the Gauss functions.

在前一篇文章中提出了二个核子空间结构对称的波函数。本文又提出了三个核子和四个核子空间结构全对称的波函数。将本文的波函数与Flowers和Redlich用壳模型计算的相应的波函数作了比较,结果发现这些波函数很相一致,波函数的重迭积分的平方都在80％以上。