X-rays from an 241Am source and their relative intensities

We report on the L and M shell Np X-ray transitions which may occur during the decay of 241Am sources. The number of X-rays per decay for more than 20 X-ray peaks, over the energy range 2–25 keV are reported. Branching ratios for the 26 and 33 keV γ-rays are also given. A simple experiment to measure the 10–20 μm ice thickness buildup on modern Si(Li) detectors is also described. This is important because the presence of a thin absorbing layer on the front face of Si(Li) detectors is critical in the 0–5 keV energy region where the Np M lines occur.