Comments on the electromagnetic decay of $\Lambda (1520)$

Abstract

The electromagnetic decay processes of excited hyperon states are a very sensitive probe of the structure of hyperons. We will argue that the recent measurements of electromagnetic decay rates indicate that the wave functions of the hyperon ground states should contain sizeable components of excited quark states (configuration mixing). Flavor-SU(3) is a broken symmetry and it appears that the hyperon wave functions should preferably be written in a $uds$-basis, where only the light $u$ and $d$ quarks are symmetrized, and not in the usual SU(6)-basis.