Recently, some interesting theoretical studies for the [B.sup.*] weak decays
have been made within the SM in [73, 74, 76-82].
Therefore, weak decays
provide a favorable testing ground in a search for such feeble forces.
An excited lepton has three possible decay modes: radiative decay [l.sup.*] [right arrow] [l.sub.[gamma]], neutral weak decay
[l.sup.*] [right arrow] lZ, and charged weak decay
[I.sup.*] [right arrow] vW.
These decay modes are radiative decay [v.sup.*] [left arrow] v[gamma], neutral weak decay
[v.sup.*] [right arrow] vZ, and charged weak decay
[v.sup.*] [right arrow] eW.
Thus, in , we had calculated the mass spectrum, weak decay
constants, two-photon decay widths and two-gluon decay widths of ground (1S) and radially excited (2S, 3S, ...) states of pseudoscalar charmonium and bottomonium such as [[eta].sub.c] and [[eta].sub.b] as well as the mass spectrum and leptonic decay constants of ground state (1S) and excited (2S, 1D, 3S, 2D, 4S, and 3D) states of vector charmonium and bottomonium such as J/[psi] and [gamma], using this formulation of 4x4 Bethe-Salpeter equation under covariant instantaneous ansatz (CIA).
(1987) Theoretical Status of weak decays
. Talk at 1987 International Symposium on Lepton and Photon Interactions at High Energies, Hamburg, 1987.
The decay amplitudes for the weak decays
, [D.sub.0] [right arrow] [K.sup.+][K.sup.*][(892).sup.-] and [D.sup.0] [right arrow] [K.sup.-][K.sup.*][(892).sup.+], will be handled with the aforementioned FAT approach [48,49].