Improved Measurement of the Electroweak Penguin Process B->Xsll

We present an improved measurement of the branching fraction for the electroweak penguin process B->Xsl+l-, where l is an electron or a muon and Xs is a hadronic system containing an s-quark. The measurement is based on a sample of 152 * 10^6 ~ Upsilon(4S) -> BB-bar events collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. The Xs hadronic system is reconstructed from one K+- or K0s and up to four pions, where at most one pion can be neutral. Summing over both lepton flavors, the inclusive branching fraction is measured to be Br(B->Xsll)=(4.11 +- 0.83(stat.) +0.74 -0.70 (syst.) )*10^{-6} for m(ll) > 0.2GeV.

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