Λ Scattering Phase shifts and CP violation in Ξ → π Λ Decay
نویسنده
چکیده
CP violating signals in weak Ξ → πΛ decay require the knowledge of πΛ Sand P-wave scattering phases at m Ξ center-of-mass energy. We have calculated these phases in baryon chiral perturbation theory with ground-state Σ in s and u channels and 3 2 + Σ(1385) in the u channel. We do not treat the baryons as heavy. We find δ S = −17.6 o and δ P = −3.1 o with the central value of the strong coupling parameter D. We also investigate the variation of the scattering phases as functions of the parameter D. We compare this result with previous calculations, and discuss its relevance to CP-asymmetry parameters.
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