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arXiv · 1710.07165

LSZ-reduction, resonances and non-diagonal propagators: fermions and scalars

Adrian Lewandowski
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Abstract

We analyze in details the effects associated with mixing of fermionic fields. In a system with an arbitrary number of Majorana or Dirac particles, a simple proof of factorizability of residues of non-diagonal propagators at the complex poles is given, together with a prescription for finding the "square-rooted" residues to all orders of perturbation theory, in an arbitrary renormalization scheme. Corresponding prescription for the scalar case is provided as well.

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Adrian Lewandowski. 2017-10-19. LSZ-reduction, resonances and non-diagonal propagators: fermions and scalars. https://doi.org/10.1016/j.nuclphysb.2018.10.020

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