Integral reaction rate measurements in /sup 252/Cf and /sup 235/U fission spectra. Final report

In support of the light water reactor pressure vessel (LWR-PV) surveillance dosimetry program established by the U.S. Nuclear Regulatory Commission, the National Bureau of Standards is undertaking a series of measurements to provide a physical basis for neutron dosimetry standards. Reaction rate measurements have been made with both 252 Cf and 235U fission neutron fields. The following reactions have been measured through an activation technique: 115In(n,n') 58Ni(n,p) and 54Fe(n,p). The neutron emission rate of the 252Cf source has been measured with the MnSO4 bath technique, thus permitting a direct measure of the spectrum averaged integral cross section for Cf. The source strength of the 235U fission neutron field has been measured relative to the 252Cf neutron field using the 115In(n,n') reaction. All measurement of cross sections in the 235U fission field are therefore relative measurements.