0 v 1 1 1 D ec 1 99 7 Evidence from QCD Sum Rules for Large Violation of Heavy Quark Symmetry in Λ b Semileptonic Decay
نویسندگان
چکیده
We set up sum rules for heavy lambda decays in a full QCD calculation which in the heavy quark mass limit incorporates the symmetries of heavy quark effective theory. For the semileptonic decay of the Λ b we find at the zero recoil point a violation of the heavy quark symmetry of more than 20%. We test the method by calculating the decay width of the semileptonic Λ c decay and obtain a reasonable agreement with experiment.
منابع مشابه
Sum Rules Calculation of Heavy Λ Semileptonic Decay
We set up sum rules for heavy lambda decays in a full QCD calculation which in the heavy quark mass limit incorporates the symmetries of heavy quark effective theory. For the semileptonic Λ c decay we obtain a reasonable agreement with experiment. For the Λ b semileptonic decay we find at the zero recoil point a violation of the heavy quark symmetry of about 20%.
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