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Lepton Asymmetries in Heavy Baryon Decays of $Λ_b\toΛl^+l^-$

Chuan-Hung Chen·C. Q. Geng
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Abstract

We study the dilepton forward-backward and the longitudinal, normal and transverse lepton polarization asymmetries in the heavy baryon decays of $Λ_b\toΛl^+l^-$. We show that the asymmetries have a less dependence on the non-perturbative QCD effects. In the standard model, we find that the integrated forward-backward asymmetries (FBAs) and three components of the polarizations in the QCD sum rule approach (pole model) are $-0.13\ (-0.12)$ and $(58.3,-9.4,-0.07)%$ ($(58.3,-12.6,-0.07)%$) for $Λ_b\toΛμ^+μ^-$ and $-0.04 (-0.03)$ and $(10.9,-10.0,-0.39)%$ ($(10.9,-0.2,-0.34)%$) for $Λ_b\toΛτ^+τ^-$, respectively.

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Chuan-Hung Chen, C. Q. Geng. 2001-03-19. Lepton Asymmetries in Heavy Baryon Decays of $Λ_b\toΛl^+l^-$. https://doi.org/10.1016/s0370-2693(01)00937-6

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