Cascade Mixing, a New Kind of Particle Mixing Phenomenon

We discuss ``cascade mixing", where one particle mixture, say a B0, leads to another, say a K0. A simple analysis is possible in the amplitude approach, which avoids ``collapses of the wavefunction" and is explicitly covariant. Some novel possibilities, both of conceptual and perhaps of experimental interest, arise. For example, we explain how such processes can allow one to ``tune", in principle, the phase relations in a particle mixture. Also, effects arise involving combinations of the mass differences of two particle mixtures. We explain how an intermediate measurement may play the role of a regenerator, so that in principle regeneration-like effects can be induced for the B0 and D0 systems, despite their short flight paths. The analysis of such process with respect to CP and the distinction between ``direct" and ``indirect" CP violation is discussed.