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Title: Measurement of the B {yields} X{sub s} {ell}{sup +}{ell}{sup -} Branching Fraction Using a Sum Over Exclusive Modes

Technical Report ·
DOI:https://doi.org/10.2172/815247· OSTI ID:815247

We present a measurement of the branching fraction for the flavor-changing neutral current process B {yields} X{sub s}{ell}{sup +}{ell}{sup -} based on a sample of 88.9 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events recorded with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. The final state is reconstructed from pairs of electrons or muons and a hadronic system consisting of one K{sup {+-}} or K{sub s}{sup 0} and up to two pions, with at most one {pi}{sup 0}. Summing over both lepton flavors, we observe a signal of 41 {+-} 10(stat) {+-} 2(syst) events with a statistical significance of 4.6 {sigma}. The inclusive branching fraction is determined to be {Beta}(B {yields} X{sub s}{ell}{sup +}{ell}{sup -}) = (6.3 {+-} 1.6(stat){sub -1.5}{sup +1.8}(syst)) x 10{sup -6} for m({ell}{sup +}{ell}{sup -}) > 0.2 GeV/c{sup 2}. All results are preliminary.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE Office of Science (US)
DOE Contract Number:
AC03-76SF00515
OSTI ID:
815247
Report Number(s):
SLAC-PUB-10100; TRN: US0304550
Resource Relation:
Other Information: Paper was contributed to the XXIst International Symposium on Lepton and Photon Interactions at High Energies, Batavia, IL (US) 08/11/2003--08/16/2003; PBD: 7 Aug 2003
Country of Publication:
United States
Language:
English