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arXiv · hep-ph/9707369

Field theory approach to K0-K0bar and B0-B0bar systems

M. Beuthe·G. Lopez Castro·J. Pestieau
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Abstract

Quantum field theory provides a consistent framework to deal with unstable particles. We present here an approach based on field theory to describe the production and decay of unstable $K^0-\bar{K^0}$ and $B^0-\bar{B^0}$ mixed systems. The formalism is applied to compute the time evolution amplitudes of $K^0$ and $\bar{K^0}$ studied in DAPHNE and CPLEAR experiments. We also introduce a new set of parameters that describe CP violation in $ K \to ππ$ decays without recourse to isospin decomposition of the decay amplitudes.

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M. Beuthe, G. Lopez Castro, J. Pestieau. 1997-07-17. Field theory approach to K0-K0bar and B0-B0bar systems. https://doi.org/10.1142/s0217751x98001682

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