The decay of141Ce

The decay of¹⁴¹Ce has been reinvestigated using different experimental methods. The efficiency extrapolation technique applied to 4πβ —γ coincidence measurements has been employed for the determination of the disintegration rate of the sources and of the total internal conversion coefficient. TheK X-ray andγ-ray emisssion rates have been measured with a calibrated Si(Li) and an intrinsic germanium detector. Additionally the photon intensities have been determined from the internal conversion coefficients. Electron experiments with a magneticβ-spectrometer yielded the relative intensities, the shape factors and the maximum energies of the two β^?-transitions and the internal conversion ratiosK/L andK/(L + M+...). TheK-shell internal conversion probability has been determined with an electronK X-ray coincidence technique using the magneticβ-spectrometer together with a high energy resolution Si(Li) detector. New values for the following decay properties have been deduced:β ^?-intensities (p ₁ =0.306 + 0.006,p ₂= 0.694±0.006), shape factorsC = const (1+Aε) (A ₁ = ?(0.24±0.03),A ₂=?(0.22±0.04)), maximumβ ^?-energies (E ₀₁ = (582.2±2.6) keV,E ₀₂= (436.7±4.6) keV),K- shell internal conversion coefficient (α _K = 0.376±0.008), total internal conversion coefficient (α = 0.438±0.010), internal conversion ratios (K/L = 7.29±0.24, K/(L + M + ...) = 5.78±0.18),γ-ray intensity (I _γ = 0.482±0.003),K X-ray intensity (I_{K X} = 0.168±0.002) and the photon intensity ratio (I _{K X} /I _γ = 0.349±0.005). The procedure of uncertainty quotation is presented in some detail. The results are discussed with respect to existing experimental data.