Independent yields of 150Pm in the thermal neutron-induced fission of 233U, 235U, 239Pu and 249Cf and cross-section for the 149Pm(n,γ)150Pm reaction

Independent yields for the shielded nuclide 150Pm were determined in the thermal neutron-induced fission of 233U, 235U, 239Pu and 249Cf using radiochemical techniques. They were found to be (2.6 +- 0.2) x 10-4%, (3 +- 1) x 10-5%, (1.15 +- 0.07) x 10-3% and (1.9 +-0.2) x 10-2%, respectively; these values correspond to empirical Zp values of 58.66, 58.31, 58.79 and 59.18, respectively, if a Gaussian charge dispersion function with a sigma of 0.56 is used. A comparison of the Zp values for 150Pm with Zp values for other nuclides in the thermal neutron-induced fission of several actinide isotopes is given. The cross-section for 149Pm(n,γ)150Pm in a swimming pool reactor neutron spectrum was found to be (1630 +- 160) barn. (author)