Evidence for the Flavor Changing Neutral Current Decays B->Kll and B->K*ll
- SLAC
The authors present preliminary results from a search for the rare, flavor-changing neutral current decays B {yields} K{ell}{sup +}{ell}{sup -} and B {yields} K*{ell}{sup +}{ell}{sup -}, where {ell}{sup +}{ell}{sup -} is either an e{sup +}e{sup -} or {mu}{sup +}{mu}{sup -} pair. The data sample comprises (84.4 {+-} 0.9) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays (77.8 fb{sup -1}) collected with the BaBar detector at the PEP-II B Factory. For B {yields} K{ell}{sup +}{ell}{sup -}, they observe a signal with estimated significance of 4.4{sigma} and obtain {Beta}(B {yields} K{ell}{sup +}{ell}{sup -}) = (0.78{sub -0.20-0.18}{sup +0.24+0.11}) x 10{sup 06} (averaged over {ell} = e and {mu}). For B {yields} K*{ell}{sup +}{ell}{sup -}, they observe an excess of events over background with estimated significance of 2.8{sigma}. They obtain {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) = (1.68{sub -0.58}{sup +0.68} {+-} 0.28) x 10{sup -6} and the 90% C.L. upper limit {Beta}(B {yields} K*{ell}{sup +}{ell}{sup -}) < 3.0 x 10{sup -6}.
- Research Organization:
- Stanford Linear Accelerator Center, Menlo Park, CA (US)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC03-76SF00515
- OSTI ID:
- 799971
- Report Number(s):
- SLAC-PUB-9323
- Country of Publication:
- United States
- Language:
- English
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