Abstract
The determination of |V cb | using inclusive and exclusive (semi-)leptonic decays exhibits a long-standing tension of varying \( \mathcal{O}\left(3\sigma \right) \) significance. For the inclusive determination the decay rate is expanded in 1/m b using heavy quark expansion, and from moments of physical observables the higher order heavy quark parameters are extracted from experimental data in order to assess |V cb | from the normalisation. The drawbacks are high correlations both theoretically as well as experimentally among these observables. We will scrutinise the inclusive determination in order to add a new and less correlated observable. This observable is related to the decay angle of the charged lepton and can help to constrain the important heavy quark parameters in a new way. It may validate the current seemingly stable extraction of |V cb | from inclusive decays or hints to possible issues, and even may be sensitive to New Physics operators.
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Turczyk, S. Additional information on heavy quark parameters from charged lepton forward-backward asymmetry. J. High Energ. Phys. 2016, 131 (2016). https://doi.org/10.1007/JHEP04(2016)131
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DOI: https://doi.org/10.1007/JHEP04(2016)131