2005/03/24 by The Belle Collaboration, M. Iwasaki, K. Itoh +96 · 10 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Neutrino Physics Research #Particle physics theoretical and experimental studies #hep-ex
paper · pdf · doi:10.1103/physrevd.72.092005
published as Phys.Rev.D72:092005,2005 · 16 pages 5 figures Latex, Submitted to Physical Review D
arxiv created 2005/03/24 · openalex publication_date 2005/11/30 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
We present an improved measurement of the branching fraction for the electroweak penguin process B\ensuremath→Xs\ensuremathℓ+\ensuremathℓ^\ensuremath-, where \ensuremathℓ 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\ifmmode×\else\texttimes\fi106 \ensuremathΥ(4S)\ensuremath→BB events collected with the Belle detector at the KEKB energy asymmetric e+e^\ensuremath- collider. The Xs hadronic system is reconstructed from one K^\ifmmode±\else\textpm\fi 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\ensuremath→Xs\ensuremathℓ+\ensuremathℓ^\ensuremath-)=(4.11\ifmmode±\else\textpm\fi0.83(stat)_\ensuremath-0.81+0.85(syst))\ifmmode×\else\texttimes\fi10^\ensuremath-6 for M_\ensuremathℓ+\ensuremathℓ^\ensuremath->0.2 GeV/c2.