Evolution of Mixed Particles Interacting with Classical Sources
  We study the systems of scalar and spinor particles with mixing emitted by external classical sources. The particles wave functions exactly accounting for external sources are obtained directly from the Lorentz invariant wave equations in (3+1)-dimensional space-time. Then we discuss sources which are localized in space and emit harmonic radiation. We obtain that the considered scalar and spinor fields can be converted from one type to another due to the presence of the vacuum mixing. This phenomenon is shown to be analogous to neutrino flavor oscillations in vacuum since the calculated transition and survival probabilities coincide with the corresponding expressions for neutrino oscillations. When we discuss the evolution of spinor particles, the situation of general mass matrix, which has both Dirac and Majorana mass terms, is studied. In this case we analyze the appearance of antiparticles in the initial particles beam. The relevance of the developed technique to the description of neutrino flavor oscillations is examined. 
Maxim Dvornikov (University of Jyv\"askyl\"a, IZMIRAN, Universidad   T\'ecnica Federico Santa Mar\'ia)