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Model-independent method for measuring the angular coefficients of B0 → D∗−τ +ντ decays

Journal of High Energy Physics volume 2019, Article number: 133 (2019) Cite this article

A preprint version of the article is available at arXiv.

Abstract

Reconstruction of the B0 → D∗−τ +ντ angular distribution is complicated by the strongly biasing effect of losing the neutrino information from both the B and τ decays. In this work, a novel method for making unbiased measurements of the angular coefficients while preserving the model independence of the angular technique is demonstrated. The twelve angular functions that describe the signal decay, in addition to background terms, are modelled in a multidimensional fit, using template probability density functions that encapsulate all resolution and acceptance effects. Sensitivities at the LHCb and Belle II experiments are estimated, and sources of systematic uncertainty are discussed, notably in the extrapolation to a measurement of R(D∗).

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Author information

Authors and Affiliations

  1. Department of Physics, University of Oxford, Parks Road, Oxford, U.K.

    Donal Hill & Malcolm John

  2. Département de Physique, Ećole Normale Supérieure, 45 Rue d’Ulm, Paris, France

    Wenqi Ke

  3. Centre de Physique des Particules de Marseille, Aix-Marseille University, 163 Avenue de Luminy, Marseille, France

    Anton Poluektov

Authors
  1. Donal Hill
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  2. Malcolm John
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  3. Wenqi Ke
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Correspondence to Donal Hill.

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ArXiv ePrint: 1908.04643

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Hill, D., John, M., Ke, W. et al. Model-independent method for measuring the angular coefficients of B0 → D∗−τ +ντ decays. J. High Energ. Phys. 2019, 133 (2019). https://doi.org/10.1007/JHEP11(2019)133

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  • DOI: https://doi.org/10.1007/JHEP11(2019)133

Keywords

  • B physics
  • Flavor physics
  • Tau Physics
  • Beyond Standard Model
  • Hadron- Hadron scattering (experiments)