Measurement of thermal neutron capture cross sections of 237Np and 242Pu using prompt gamma neutron activation

Several samples of Np-237 and Pu-242 were irradiated in the guided cold neutron beam of the prompt gamma activation analysis facility at the Budapest Research Reactor. The thermal neutron capture cross sections of Np-237 and Pu-242 were evaluated from the obtained prompt and delayed gamma ray data. The thermal neutron capture cross sections for Np-237(n,gamma)Np-238 was found to be sigma(0)(Np-237) = 170.4 +/- 7.4b and for Pu-242(n,gamma)Pu-243 to be sigma(0)(Pu-242) = 19.6 +/- 3.9b.