Unitarity relations and their application to meson-antimeson mixing - art.no. 017501

The Hermiticity of the full Hamiltonian constrains the various structural p roperties (such as f <-> (f) over bar oscillations) of the complex formed b y a neutral flavored meson f and its antiparticle (f) over bar. These "unit arity'' constraints are written, following Kabir and Pilaftsis. The evaluat ion of the structural amptitudes at small values of the proper time brings out the inadequacy of the usual phenomenology based on the Weisskopf-Wigner approximation. Some known asymmetries could experimentally check this in t he future. [S0556-2821(99)01511-8].