On the Topological Skyrme Model with Wess-Zumino Anomaly Term and the Nucleus

Syed Afsar Abbas (JMI University New Delhi)

The electric charge of the nucleus $Q = T_z + A = T_z + Z+N$ has not been derived ab initio, by any of the currently successful models of the nucleus. Another issue, that of why of all the hyper-nuclei experimentally observed so far, the $\Lambda$-hyperon seems to dominate, has no proper explanation within conventional understanding within current nuclear models. Here we shall show that these two problems are well understood within the topological Skyrme-Wess-Zumino model. Two flavour topological Skyrme model has been focus of much work in recent years in studies of the nucleus. Some of the well-known basic issues, like understanding of the fermion character and the baryon number of the nucleon, demand going over to three flavours, and that brings in the Wess-Zumino anomaly term in a fundamental manner. Our model here, the Skyrme-Wess-Zumino model, is the Skyrme lagrangian supplemented with the Wess-Zumino anomaly term. It is commonly believed that spin-half octet and spin three-half decuplet are the lowest dimensional representations that the three-flavour Skyrmions would correspond to. We study the effect of including the electric charges consistently in this analysis. We show that indeed this leads to a significant improvement in our understanding of proper reprentations of two-flavour and three-flavour Skyrmionic representations. A better understanding of the nuclear structure is thus provided by our model.