Joint description of weak radiative and nonleptonic hyperon decays in broken SU(3)

Abstract

We give a joint description of weak radiative (WR) and nonleptonic (NL) hyperon decays (HD) in broken SU(3). The two groups of decays are linked via SU(2){sub W} spin symmetry and vector-meson dominance (VMD). We use experimental information on the parity-conserving NLHD amplitudes to fix the corresponding WRHD amplitudes. With the latter known, the data on the WRHD branching ratios and asymmetries permit us to determine the parity-violating WRHD amplitudes in terms of two parameters corresponding to the two-quark and single-quark transitions. We obtain a good description of the data, and, in particular, a large {sigma}{sup +}{yields}p{gamma} asymmetry. Then, using the SU(2){sub W}+VMD route we determine the non-soft-meson correction term in the parity-violating NLHD amplitudes. The latter is shown to subtract a substantial amount from the current-algebra commutator thus leading towards the resolution of the S ratio P discrepancy in NLHD.