Determination of plutonium content and isotopic ratios in environmental samples by L x-ray and α-particle measurements

The analytical separation of 239Pu and 240Pu in environmental samples by α-particle spectrometry is usually not possible because of the small differences of the α-energies. This problem is solved by additional measurements of the L x-rays emitted from the same sources taking into account the different emission probabilities of L x-rays for 239Pu and 240Pu. The analysis method has been tested by measurements on synthetic sources with known activity ratios. Several soil samples with contaminations of different origin have been analysed for their plutonium content and isotopic ratios.