The single state dominance hypothesis and the two-neutrino double beta decay of Mo-100

The hypothesis of the single state dominance (SSD) in the calculation of th e two-neutrino double beta decay (2 nu beta beta -decay) of Mo-100 is teste d by an exact consideration of the energy denominators of the perturbation theory. Both transitions to the ground state as well as to the 0(+) and 2() excited states of the final nucleus Ru-100 are considered. We demonstrate that by experimental investigation of the single electron energy distribut ion and the angular correlation of the outgoing electrons, the SSD hypothes is can be confirmed or ruled out by a precise 2 nu beta beta -decay measure ment (e.g. by NEMO III collaboration).