Determination of long-lived radionuclides in water by alpha spectrometry

This study consists of two parts. The first part deals with the prevention of the silicondetectors contamination for low-level alpha spectrometry by recoil nuclides, which is a seriousproblem in the measurement of alpha emitters. In this order, we describe the production of the thinformvar films as stopper foils for recoil nuclei. In the second part, analysis of 226Ra using alphaspectrometry is presented. The requirement for the determination of radium has become a matter ofinterest in public health due to its hazardous nature with respect to internal exposure. A fast andsimple procedure based on sorption of Ra on MnO2 coated discs which can be used directly for α-spectrometry without the need of further separation and preparation methods is described. Themeasurements were performed with an ORTEC SOLOIST alpha spectrometer with PIPS detector. Usingthis method a very good resolution of the alpha spectra was obtained (~23 keV). The reproducibilityof the sorption uptake behavior was investigated using samples prepared from a standard radiumsolution.