Interactions Between Baryon And Baryon With Strangeness Being-2

Quantum chromodynamics?QCD?is the basic theory of strong interaction,and the phenomenological models with QCD spirit—chiral SU?3?quark model??-SU?3?QM?and extended chiral SU?3?quark model?Ex.?-SU?3?QM?have achieved very good results when studying the structures of hadrons and strong interactions.Inspired by H particle,this thesis have studied the interactions of??,N?and??dibaryon systems with strangeness being-2 by resonant group method?RGM?in the framework of these two quark models.We first study the effective potentials and binding energies of the??,N?and??systems with different spins and isospins.The results show that:1)The??_?0,0?and??_?1,0?systems cannot form bound states in the above two models,which is consistent with results from other theoretical methods.The internal medium-range interactions of these two systems are relatively weak attraction,which mainly comes from?meson exchange.The short-range behaviors of single gluon exchange??-SU?3?QM?and vector mesons exchanges?Ex.?-SU?3?QM?are similar and they are repulsive.2)The N?_?0,0?system can form a bound state in the two models,and its binding energy is about 21-33 MeV.The effective potential of the N?_?0,0?system is strong attraction,and the short-range one gluon exchange??-SU?3?QM?is relatively weak attraction and vector mesons exchanges?Ex.?-SU?3?QM?are repulsive forces.Therefore,this attraction is mainly provided by?meson exchange.N?_?1,0?,N?_?0,1?and N?_?1,1?systems cannot form bound states in two models.The internal interaction of these three systems are relatively weak attraction in the middle-range part,which is mainly provided by?meson exchange;The short-range behaviors of single gluon exchange??-SU?3?QM?and vector mesons exchanges?Ex.?-SU?3?QM?are similar and they are repulsive.Our current results show that the N?_?0,0?bound state is crucial for understanding the structure of H-particles.3)The??_?0,0?and??_?1,0?systems are bound states in two models,and their binding energies are 15-26 MeV and 22-62 MeV,respectively.The internal interactions of the two systems are relatively strong attraction,and the attractive force of the??_?1,0?system is greater than that of the??_?0,0?system.In the??_?0,0?system,the short-range behaviors of single gluon exchange??-SU?3?QM?and vector mesons exchanges?Ex.?-SU?3?QM?are similar,and they are attractive;The medium-long-range part is mainly due to?meson exchange.In the??_?1,0?system,the single gluon exchange??-SU?3?QM?is repulsive,and the vector mesons exchanges?Ex.?-SU?3?QM?are attractive,which means that their short-range behaviors are different;the medium-long-range interaction mainly comes from?meson exchange.The results of the study show that the single channel??_?0,0?is important for understanding the structure of H particles.4)The??_?0,1?,??_?1,1?and??_?0,2?systems cannot form bound states in both models.The internal interactions of these three systems are relatively weak attraction in the middle range,which mainly comes from?meson exchange.The short-range behaviors of single gluon exchange??-SU?3?QM?and vector mesons exchanges?Ex.?-SU?3?QM?are similar and they are repulsive.At the same time,we also study the S-,P-and D-wave scattering phase shifts,total scattering cross sections and contributions of S-,P-and D-wave to total cross section of all the above systems and find that the information given by the S-wave scattering phase shifts is qualitatively consistent with that from the systems'interactions and bound energies,the P-wave interaction is weak,and the D-wave has no effect at all;The S-wave contributes the most to the total cross section,the P-wave contribution is relatively small,and the D-wave has almost no contribution.