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arXiv · hep-ph/9309225

Damping Rate of a Fermion in a Medium

J. C. D'Olivo·Jose F. Nieves
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Abstract

We examine the relation between the damping rate of a massless, chiral fermion that propagates in a medium, and the rate $Γ$ of approach to equilibrium. It is proven that these quantities are equal, by showing that they are given by the same formula in terms of the imaginary part of the self-energy evaluated at the energy of the propagating fermion mode. This result is valid provided $Γ$ is defined by using the appropriate wave functions of the mode.

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J. C. D'Olivo, Jose F. Nieves. 1995-05-19. Damping Rate of a Fermion in a Medium. https://doi.org/10.1103/physrevd.52.2987

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