ep - p h / 98 05 41 6 v 1 2 1 M ay 1 99 8 UCSD / PTH 98 – 17 hep - ph / 9805416 SU ( 3 ) symmetry breaking in hyperon semileptonic decays
نویسنده
چکیده
Flavor SU(3) symmetry breaking in the hyperon semileptonic decay formfactors is analyzed using the 1/Nc expansion. A detailed comparison with experimental data shows that corrections to f1 are approximately 10%, which agrees with theoretical expectations. Corrections to g1 are compatible with first-order symmetry breaking. A fit to the experimental data allows one to predict the g1 form factor for Ξ 0 → Σ+ decay. The proton matrix element of the T 8 component of the axial current (which is equal to 3F − D in the SU(3) symmetry limit) is found to be ≈ 0.34. Typeset using REVTEX ∗On leave from Departamento de F́ısica, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, 07000, México, Distrito Federal, Mexico
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