Measurement of the branching ratio of B0 →d∗+τ- ν τ relative to B 0 →d∗+ℓ −νℓ decays with a semileptonic tagging method

Belle Collaboration

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We report a measurement of the ratio R(D∗)=B(B0→D∗+τ-ντ)/B(B0→D∗+ν), where denotes an electron or a muon. The results are based on a data sample containing 772×106 BB pairs recorded at the (4S) resonance with the Belle detector at the KEKB e+e- collider. We select a sample of B0B0 pairs by reconstructing both B mesons in semileptonic decays to D∗ ±. We measure R(D∗)=0.302±0.030(stat)±0.011(syst), which is within 1.6σ of the Standard Model theoretical expectation, where the standard deviation σ includes systematic uncertainties. We use this measurement to constrain several scenarios of new physics in a model-independent approach.

Original languageEnglish
Article number072007
JournalPhysical Review D
Issue number7
Publication statusPublished - 2016 Oct 27

Bibliographical note

Funding Information:
Support statement: This work is supported by the Health Effects Institute (4954-RFA14-3/16-5-3) and a grant from the China Scholarship Council (201806010406). SALT and TwinGene are substudies of The Swedish Twin Registry (STR) which is managed by Karolinska Institutet and receives additional funding through the Swedish Research Council under grant 2017-00641. Funding information for this article has been deposited with the Crossref Funder Registry.

Funding Information:
Acknowledgements: Research described in this article was conducted under contract to the Health Effects Institute (HEI), an organisation jointly funded by the US Environmental Protection Agency (EPA) (assistance award number R-82811201) and certain motor vehicle and engine manufacturers. The contents of this article do not necessarily reflect the views of HEI, or its sponsors, nor do they necessarily reflect the views and policies of the EPA or the motor vehicle and engine manufacturers. The authors would also like to thank all participants in the CEANS, DCH and DNC cohort studies, and the respective study teams (the ELAPSE project) for their hard work and effort. Thanks to Niklas Andersson (Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden) for the work of harmonising complicated data on covariates between the four subcohorts in CEANS.

Publisher Copyright:
© 2016 American Physical Society.

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)


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