We present the first result for the hyperon vector form factor f 1 for Ξ0→Σ+lν̄ and Σ-→nlν̄ semileptonic decays from fully dynamical lattice QCD. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of dynamical domain-wall fermions and the Iwasaki gauge action at β=2.13, corresponding to a cutoff a-1=1.73GeV. Our results, which are calculated at the lighter three sea quark masses (the lightest pion mass down to approximately 330 MeV), show that a sign of the second-order correction of SU(3) breaking on the hyperon vector coupling f1(0) is negative. The tendency of the SU(3)-breaking correction observed in this work disagrees with predictions of both the latest baryon chiral perturbation theory result and large Nc analysis.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - 2012 Dec 3|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)