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Evidence for an Excess of B → D^(*)τ^-ν_τ Decays

Lees, J. P. and Chao, D. S. and Cheng, C. H. and Doll, D. A. and Echenard, B. and Flood, K. T. and Hitlin, D. G. and Ongmongkolkul, P. and Porter, F. C. and Rakitin, A. Y. (2012) Evidence for an Excess of B → D^(*)τ^-ν_τ Decays. Physical Review Letters, 109 (10). Art. No. 101802. ISSN 0031-9007. doi:10.1103/PhysRevLett.109.101802.

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Based on the full BABAR data sample, we report improved measurements of the ratios R(D^(*))=B(B → D^(*)τ^-ν_τ)/B(B → D^(*)ℓ_ℓ^-ν_ℓ), where ℓ is either e or μ. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D^*)=0.332±0.024±0.018, which exceed the standard model expectations by 2.0σ and 2.7σ, respectively. Taken together, our results disagree with these expectations at the 3.4σ level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

Item Type:Article
Related URLs:
URLURL TypeDescription
Cheng, C. H.0000-0002-8382-0447
Hitlin, D. G.0000-0003-4028-6982
Porter, F. C.0000-0003-1948-8889
Additional Information:© 2012 American Physical Society. Received 31 May 2012; published 6 September 2012. We acknowledge M. Mazur for his help throughout the analysis and S. Westhoff, S. Fajfer, J. Kamenik, and I. Nišandžić for their help with the calculation of the charged Higgs contributions. We are grateful for the excellent luminosity and machine conditions provided by our PEPII colleagues and for the substantial dedicated effort from the computing organizations that support BABAR. The collaborating institutions thank SLAC for its support and kind hospitality. This work is supported by DOE and NSF (USA), NSERC (Canada), CEA and CNRS-IN2P3 (France), BMBF and DFG (Germany), INFN (Italy), FOM (Netherlands), NFR (Norway), MES (Russia), MICIIN (Spain), and STFC (United Kingdom). Individuals have received support from the Marie Curie EIF (European Union) and the A. P. Sloan Foundation (USA).
Funding AgencyGrant Number
Department of Energy (DOE)UNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Commissariat à l’Energie Atomique (CEA)UNSPECIFIED
Istituto Nazionale di Fisica Nucleare (INFN)UNSPECIFIED
Stichting voor Fundamenteel Onderzoek der Materie (FOM)UNSPECIFIED
Norwegian Research CouncilUNSPECIFIED
Ministry of Education and Science of the Russian FederationUNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
Marie Curie FellowshipUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Institut National de Physique Nucléaire et de Physique des Particules (IN2P3)UNSPECIFIED
Deutsche Forschungsgemeinschaft (DFG)UNSPECIFIED
Issue or Number:10
Classification Code:PACS: 13.20.He, 14.40.Nd, 14.80.Da
Record Number:CaltechAUTHORS:20121018-103620332
Persistent URL:
Official Citation:Evidence for an Excess of B →D(*)τ-ν τ Decays J. P. Lees et al. (BABAR Collaboration) Published 6 September 2012 (8 pages) 101802
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34972
Deposited By: Ruth Sustaita
Deposited On:18 Oct 2012 18:15
Last Modified:09 Nov 2021 23:11

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