We calculate magnetic transition moments in the chiral quark-soliton model, with explicit SU(3)-symmetry breaking taken into account. The dynamical model parameters are fixed by experimental data for the magnetic moments of the baryon octet and from the recent measurements of $\Theta^{ +}$ mass. Known magnetic transition moments $\mu_{ \Lambda\Sigma}$, $\mu_{ N\Delta}$ are reproduced and predictions for other octet-decuplet and octet-antidecuplet transitions are given. In particular $\mu_{ \Sigma\Sigma^{ \ast}}$ recently constrained by SELEX is shown to be below $0.82 \mu_N$. The recent GRAAL data on $\eta$ photoproduction off the nucleon are explained in terms of a new narrow antidecuplet neutron-like resonance.
Categories: hep-ph