Formfaktor des β-Spektrums von99Tc

The β-spectrum of the second non-unique forbidden 9/2⁺?5/2⁺ transition in the decay of⁹⁹Tc has been investigated with a 4π – Si (Li)-semiconductor-spectrometer. The shape factor has been determined: S(W)=k (1?3.97 W+1.15/W+3.05 W²). It was also possible to fit the data with the normal ξ-Approximation to the theoretical shape factorS(W)=k(q¹²+0.54 p²). The second forbidden 2⁺? 0⁺ β^?-transition in the decay of³⁶Cl was reinvestigated to test the spectrometer as well as the fitting-technique.