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Lepton Polarization Asymmetry in $B\to K^{(*)} l^+l^-$

C. Q. Geng·C. P. Kao
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Abstract

We investigate the longitudinal lepton polarization asymmetry in the exclusive processes $B\to K l^+l^-$ and $B\to K^* l^+l^-$. We include both short and long-distance contributions to the asymmetry in our discussions. We find that average values of the polarization asymmetries of the muon and tau for $B\to K^{(*)}μ^+μ^-$ and $B\to K^{(*)}τ^+τ^-$ are $-0.8\ (-0.7)$ and $-0.2\ (-0.5)$, respectively.

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C. Q. Geng, C. P. Kao. 1996-08-28. Lepton Polarization Asymmetry in $B\to K^{(*)} l^+l^-$. https://doi.org/10.1103/physrevd.54.5636

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