Journal of High Energy Physics

, 2017:61 | Cite as

R(D), |Vcb|, and the Heavy Quark Symmetry relations between form factors

  • Dante Bigi
  • Paolo Gambino
  • Stefan SchachtEmail author
Open Access
Regular Article - Theoretical Physics


Stringent relations between the B(∗)D(∗) form factors exist in the heavy quark limit and the leading symmetry breaking corrections are known. We reconsider their uncertainty and role in the analysis of recent Belle data for BD(∗)ν with model-independent parametrizations and in the related prediction of R(D(∗)). We find |Vcb| = 41.5(1.3) 10−3 and |Vcb| = 40.6( − 1.3 + 1.2 ) 10−3 using input from Light Cone Sum Rules, and R(D) = 0.260(8).


Heavy Quark Physics Quark Masses and SM Parameters 


Open Access

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  1. 1.Dipartimento di FisicaUniversità di Torino & INFNTorinoItaly

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