Electromagnetic, axial-vector, and strange currents in the Skyrme model: Effects of symmetry breaking

Abstract

We further discuss a recently proposed approach to treating the SU(3) Skyrme model which led to good predictions for the baryon mass splittings. The baryon matrix elements of vector and axialvector currents are studied in great detail. It is found that the spin-½ baryon magnetic moments and the various $\frac{g_A}{g_V}$ ratios of hyperon decays approximately obey the SU(3)-symmetry relations. This fact only emerges after taking into account some very complicated and previously neglected terms. This result is remarkable in the sense that the baryon wave functions in the model differ appreciably from SU(3) symmetry. On the other hand, there are important deviations from SU(3) invariance for matrix elements of strange currents in the nucleon. The latter are relevant for some experiments of great current interest and our predictions for them are presented and compared with other approaches.