Oscillations of recoil particles against mixed states

Some consequences of the oscillations of neutral kaons and neutrinos are discussed, in particular, the possibility of oscillations of particles recoiling against kaons or neutrinos from the production process. We show that there are no stationary oscillations of these recoil particles in any order, and that the apparent long-wavelength oscillations, which might appear to result when an earlier treatment of ours was taken to higher order, are spurious. We show that the recoil particles may show a travelling interference pattern. It may be possible to observe this pattern for $\Lambda$s produced in a reaction, but there seems to be little hope of observing this for the case of neutrinos from muon decay.