An investigation into the 113Cd beta decay spectrum using a CdZnTe array

We present 11 independent measurements of the half-life and spectral shape of the 4-fold forbidden beta decay of 113Cd using CdZnTe semiconductors with a total combined lifetime of 6.58 kg days. Our overall result gives a half-life of (8.00±0.11(stat)±0.24(sys))×1015 years and a Q-value of 322.2±0.3(stat)±0.9(sys)keV. For the first time half-lives well beyond 1010 years have been deduced with a statistically representative sample of independent measurements.