Suche nach Strahlungsprozessen zweiter Ordnung beim Zerfall von Ag109m

The decay of an excited state by the emission of twoγ-quanta (γ γ-transitions) or two conversion electrons (e e-transitions) or oneγ-quantum and one conversion electron (γ e-transitions) is expected as a second order radiation process. The decay of Ag^109m was examined for such events using a special arrangement of two NaJ-scintillation counters in coincidence. The energies of coincident quanta were displayed on the two axes of an “X-Y”-Oscilloscope respectively. For the ratio ofγ γ-transitions to one-quantum transitions an upper limit of(frac{{W_{gamma gamma } }}{{W_gamma }} leqq 1,9 cdot 10^{ - 5} ) was obtained. Furthermore theγ-spectrum in coincidence withK X-rays was studied. From these measurementse e- andγ e-transition rates can be calculated for the case ofK shell conversion. The results obtained are:

$$frac{{W_{^e K^e K} }}{{W_gamma }} = left( {8,1_{ - 1,7}^{ + 0,6} } right) cdot 10^{ - 3} andfrac{{W_{gamma ^e K} }}{{W_gamma }}< 1,5 cdot 10^{ - 3} .$$