Mass spectrometric determination of [sup.234]U/[sup.238]U ratio with improved precision

A new mass spectrometric method is proposed for measurement of [sup.234]U/[sup.238]U ratio with a single Daly electron multiplier detector using the general peak jump method. The method is based on precise measurement of the [sup.235]U/ [sup.238]U ratio and [sup.234]U/[sup.235]U ratio, which are used to calculate the [sup.234]U/[sup.238]U ratio using the equation [sup.234]U/[sup.238]U= [sup.235]U/ [sup.238]U x [sup.234]U/[sup.235]U. The results show a significant improvement, i.e., more than 35 times better precision in measuring the [sup.234]U/[sup.238]U ratio with this method ([sigma] = 2.9 x [10.sup.8]) as compared to direct measurement of [sup.23]U/[sup.238]U ([sigma] : 1.1 x [10.sup.-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.