ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2005, vol. 72, p. -
Improved measurement of the electroweak penguin process B→Xs+-
We present an improved measurement of the branching fraction for the electroweak penguin process B→Xs+-, where is an electron or a muon and Xs is a hadronic system containing an s-quark. The measurement is based on a sample of 152×106 Υ(4S)→BB̄ events collected with the Belle detector at the KEKB energy asymmetric e+e- collider. The Xs hadronic system is reconstructed from one K± or KS0 and up to four pions, where at most one pion can be neutral. Averaging over both lepton flavors, the inclusive branching fraction is measured to be B(B→Xs+-)=(4.11±0.83(stat)-0.81+0. 85(syst))×10-6 for M+->0.2GeV/c2. © 2005 The American Physical Society.