相对论夸克模型和N-Δ能量劈裂  

Relativistic Quark Model and the N-Δ Mass Splitting

作　　者：冯庆国[1] 董宇兵[1] 

机构地区：[1]中国科学院高能物理研究所,北京100039

出　　处：《高能物理与核物理》2002年第1期21-27,共7页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金 ( 1 0 0 75 0 5 6 ) ;科学院基金和教育部基金资助~~

摘　　要：基于相对论夸克模型 ,在夸克层次上研究了N Δ的质量和二者的能量劈裂 ,通过引入了赝标量π介子云效应 ,得到了π和核子之间的耦合常数gπNN,以及单胶子交换势和单π介子交换势分别对N Δ能量劈裂的贡献 ,计算结果较好地与实验值得到了吻合 .另外我们还比较了相对论与非相对论夸克模型在处理上的不同 .In the constituent quark model, light baryons are considered as the systems of the constituent quarks with confining interaction and with a chiral interaction mediated by Goldstone bosons. Here the masses of the N and Δ and their splitting are investigated based on a relativistic quark model approach with inclusion of pion meson cloud. Pseudoscalar π-quark interaction is employed to study the coupling between the mucleon and the π. The results show the contributions of the one-gluon-exchange potential and of the pion meson cloud to the N-Δ mass splitting. Moreover, our numerical analyses indicate a difference between the relativistic and the nonrelativistic treatments.

关 键 词：相对论夸克模型 核子质量 能量劈裂 重子谱 重子 介子 耦合常数 π介子云效应 

分 类 号：O572.33[理学—粒子物理与原子核物理] O572.34[理学—物理]