A method of simultaneous determination of natural concentration of 226Ra and 14C in water samples

This paper presents the method of simultaneous determination of 226Ra and radiocarbon concentration in water samples with the use of CO2-filled proportional counter. The measurement of radon activity is performed in a proportional counter simultaneously with the measurement of the activity of radiocarbon. The accuracy of determination of radium concentration in a sample is equal to 20% when radium concentration is of the order of 10-12g/l. The minimum measurable radium concentration is limited practically only by the radium content in chemicals used and is estimated to be ca. 10-15g/l. (author)