C. Giunti et al., TREATMENT OF NEUTRINO OSCILLATIONS WITHOUT RESORT TO WEAK EIGENSTATES, Physical review. D. Particles and fields, 48(9), 1993, pp. 4310-4317
We discuss neutrino oscillations in the framework of the quantum field
theory without introducing the concept of neutrino weak eigenstates.
The external particles are described by wave packets and the different
mass eigenstate neutrinos propagate between the production and detect
ion interactions, which are macroscopically localized in space-time. T
he time-averaged cross section, which is the measurable quantity in th
e usual experimental setting, is calculated. It is shown that only in
the extremely relativistic limit can the usual quantum mechanical osci
llation probability be factored out of the cross section.