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arXiv · hep-ph/9906300

Reanalysis of the Four-Quark Operators Relevant to Λ_b Lifetime from QCD Sum Rule

Chao-Shang Huang·Chun Liu·Shi-Lin Zhu
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Abstract

Λ_b matrix element of four-quark operator relevant to its lifetime is reanalyzed by QCD sum rule. The new ingredients introduced are that (1) more vacuum condensates are considered; (2) different quark-hadron duality is adopted; and (3) the possible deviation from the vacuum saturation assumption for the four quark condensates is considered. With κ_1=4 the related hadronic parameter r is calculated to be 3.6 \pm 0.9, and the lifetime ratio τ(Λ_b)/τ(B^0) = 0.83 \pm 0.04, which is consistent with the experimental data.

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Chao-Shang Huang, Chun Liu, Shi-Lin Zhu. 2000-02-05. Reanalysis of the Four-Quark Operators Relevant to Λ_b Lifetime from QCD Sum Rule. https://doi.org/10.1103/physrevd.61.054004

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