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Measurements of branching fractions, rate asymmetries, and angular distributions in the rare decays B→Kℓ^+ℓ^- and B→K^*ℓ^+ℓ^-

Aubert, B. and Albert, J. and Chen, E. and Dvoretskii, A. and Hitlin, D. G. and Narsky, I. and Piatenko, T. and Porter, F. C. and Ryd, A. and Samuel, A. (2006) Measurements of branching fractions, rate asymmetries, and angular distributions in the rare decays B→Kℓ^+ℓ^- and B→K^*ℓ^+ℓ^-. Physical Review D, 73 (9). Art. No. 092001. ISSN 2470-0010.

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We present measurements of the flavor-changing neutral current decays B→Kℓ^+ℓ^- and B→K^*ℓ^+ℓ^-, where ℓ^+ℓ^- is either an e^+e^- or μ^+μ^- pair. The data sample comprises 229×10^6  Υ(4S)→BB decays collected with the BABAR detector at the PEP-II e^+e^- storage ring. Flavor-changing neutral current decays are highly suppressed in the standard model and their predicted properties could be significantly modified by new physics at the electroweak scale. We measure the branching fractions B(B→Kℓ^+ℓ^-)=(0.34±0.07±0.02)×10^(-6), B(B→K^*ℓ^+ℓ^-)=(0.78-0.17^(+0.19)±0.11)×10^(-6), the direct CP asymmetries of these decays, and the relative abundances of decays to electrons and muons. For two regions in ℓ^+ℓ^- mass, above and below m_(J/ψ), we measure partial branching fractions and the forward-backward angular asymmetry of the lepton pair. In these same regions we also measure the K^* longitudinal polarization in B→K^*ℓ^+ℓ^- decays. Upper limits are obtained for the lepton-flavor-violating decays B→Keμ and B→K^*eμ. All measurements are consistent with standard model expectations

Item Type:Article
Related URLs:
URLURL TypeDescription
Hitlin, D. G.0000-0003-4028-6982
Porter, F. C.0000-0003-1948-8889
Additional Information:© 2006 American Physical Society. Received 4 April 2006; published 5 May 2006. We are grateful for the excellent luminosity and machine conditions provided by our PEP-II colleagues, and for the substantial dedicated effort from the computing organizations that support BABAR. The collaborating institutions wish to thank SLAC for its support and kind hospitality. This work is supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF and DFG (Germany), INFN (Italy), FOM (The Netherlands), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from CONACyT (Mexico), Marie Curie EIF (European Union), the A. P. Sloan Foundation, the Research Corporation, and the Alexander von Humboldt Foundation.
Funding AgencyGrant Number
Department of Energy (DOE)UNSPECIFIED
NSERC (Natural Sciences and Engineering Research Council of Canada)UNSPECIFIED
CEA (Commissariat à l'Energie Atomique), FranceUNSPECIFIED
BMBF (Bundesministerium für Bildung und Forschung), GermanyUNSPECIFIED
INFN (Istituto Nazionale di Fisica Nucleare), ItalyUNSPECIFIED
FOM (The Netherlands)UNSPECIFIED
Marie Curie EIF (European Union)UNSPECIFIED
A. P. Sloan FoundationUNSPECIFIED
Research CorporationUNSPECIFIED
Alexander von Humboldt FoundationUNSPECIFIED
Issue or Number:9
Classification Code:PACS: 13.25.Hw, 13.20.He
Record Number:CaltechAUTHORS:20110211-140242318
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Official Citation:Measurements of branching fractions, rate asymmetries, and angular distributions in the rare decays B→Kℓ+ℓ- and B→K*ℓ+ℓ- B. Aubert et al. (BABAR Collaboration)
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:22147
Deposited By: Ruth Sustaita
Deposited On:11 Feb 2011 23:21
Last Modified:09 Mar 2020 13:18

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