Tests of SU(3) Symmetry-Breaking for Baryonic Beta Transitions in the Standard Model

Abstract

It is generally assumed that deviations from flavor SU(3) symmetry arise entirely from quark mass-differences, reflected in the mass splittings between strange and nonstrange members of the same SU(3) multiplet. Under this assumption, a parametrization is proposed which expresses the ratios of Gamow-Teller to Fermi matrix elements for nucleon and hyperon beta decays entirely in terms of two SU(3)-invariant coupling constants $F$ and $D$ and two parameters $\gamma$ and $\delta$ representing SU(3) breaking effects. Therefore, in principle, measurement of this ratio for any four beta-transitions should yield all four parameters. Available data do not show any evidence for SU(3) breaking. Improved measurements, also for transitions not previously measured, would provide more stringent tests.

arXiv comment9 pages, 2 tables, a few minor corrections in references