Mass spectrometric determination of U-234/U-238 ratio with improved precision

摘要

A new mass spectrometric method is proposed for measurement of U-234/U-238 ratio with a single Daly electron multiplier detector using the general peak jump method. The method is based on precise measurement of the U-235/ U-238 ratio and U-234/U-235 ratio, which are used to calculate the U-234/U-238 ratio using the equation U-234/U-238 = U-235/ U-238 x U-234/U-235. The results show a significant improvement, i.e., more than 35 times better precision in measuring the 234U/238U ratio with this method (sigma = 2.9 x 10(-8)) as compared to direct measurement of 234U/238U (sigma = 1.1 x 10(-6)). The method widens the applicability of the single collector system, and it will potentially be helpful to improve the precision in the case of the static multicollector system also.