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arXiv · hep-ph/9805201

Mixing of two-level unstable systems

G. Lopez Castro·J. H. Munoz·J. Pestieau
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Abstract

Unstable particles can be consistently described in the framework of quantum field theory. Starting from the full S-matrix amplitudes of B^+ --> (2 pi, 3 pi) l nu decays as examples in the energy region where the rho-omega resonances are dominating, we propose a prescription for the mixing of two quasi `physical' unstable states that differs from the one obtained from the diagonalization of the M -i*Gamma/2 non-hermitian hamiltonian. We discuss some important consequences for CP violation in the K_L - K_S system.

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G. Lopez Castro, J. H. Munoz, J. Pestieau. 1998-05-06. Mixing of two-level unstable systems. https://doi.org/10.1007/s100529900041

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