Oscillations of neutrinos and mesons in quantum field theory
Beuthe, M
Abstract
The controversies regarding the oscillation formula are reviewed. The different existing quantum field treatments of oscillations are reconciled by a thorough study of the external wave packet model. Stationary models are shown to be a particular case of this model. All decoherence terms are computed explicitly, so that it becomes clear that the coherence length tends to infinity in the stationary limit. Decoherence is shown to originate not only in the separation of wave packets, but also in their dispersion. Relativistic and nonrelativistic oscillating particles are treated on the same footing. The oscillation formula is derived for an unstable particle within the same formalism. Finally, correlated oscillations are discussed in detail.