235U fission product yields in the rare earth region

Abstract

Results are given of measurements of fission product yields from ²³⁵U made by an integral mass spectroscopic method allowing simultaneous determination of the concentrations of several elements in a mixture. Using this method, the yields of ¹³⁹La, ¹⁴¹Pr, ¹⁴⁷Pm and ¹⁴⁹Pm were measured for the first time. Absorption cross-sections of ¹⁴⁷Pm and ¹⁴⁷Sm are calculated from the data and a lower limit for the absorption cross-section of ¹⁴⁹Sm is estimated.