X. Song et al., F D RATIO IN HYPERON BETA-DECAYS AND THE SPIN DISTRIBUTION IN THE NUCLEON/, Physical review. D. Particles and fields, 54(3), 1996, pp. 2108-2113
It is shown that hyperon beta decay data can be well accommodated with
in the framework of Cabibbo's SU(3) symmetric description if one allow
s for a small SU(3) symmetry breaking proportional to the mass differe
nce between strange and nonstrange quarks. The F/D ratio does not depe
nd sensitively on the exact form of the symmetry breaking, and the bes
t fits are close to the value previously used in the analysis of deep
inelastic scattering of electrons or muons on polarized nucleons. The
total quark helicity and strange quark polarization in the nucleon are
discussed.