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arXiv · hep-ex/0603018

Measurement of Forward-Backward Asymmetry and Wilson Coefficients in $B \to K^* \ell^+ \ell^-$

A. Ishikawa
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Abstract

We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients $A_9/A_7$ and $A_{10}/A_7$ in $B \to K^* \ell^+ \ell^-$, where $\ell$ represents an electron or a muon. We observe a large integrated forward-backward asymmetry with a significance of 3.4$σ$. The results are obtained from a data sample containing 386 $\times 10^6$ $B\bar{B}$ pairs that were collected on the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider.

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A. Ishikawa. 2006-03-09. Measurement of Forward-Backward Asymmetry and Wilson Coefficients in $B \to K^* \ell^+ \ell^-$. https://doi.org/10.1103/physrevlett.96.251801

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