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

A preprint version of the article is available at arXiv.


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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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).

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