# (A)symmetries of weak decays at and near the kinematic endpoint

@article{Hiller2013AsymmetriesOW, title={(A)symmetries of weak decays at and near the kinematic endpoint}, author={Gudrun Hiller and Roman Zwicky}, journal={Journal of High Energy Physics}, year={2013}, volume={2014}, pages={1-33} }

A bstractAt the kinematic endpoint of zero recoil physical momenta are parallel which leads to symmetries in the decay distributions. We implement this observation for decays of the type A → (B1B2)C by extending the helicity formalism to include an unphysical timelike polarisation. The symmetries of the helicity amplitudes are worked out for a generic dimension six Hamiltonian for a B → V ℓℓ decay type. We obtain exact predictions for angular observables, e.g., for the fraction of…

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