Prompt fission neutron data calculation using experimental fission fragment charge distributions in the frame of the Point by Point treatment

Abstract

The experimental fission fragment (FF) mass distributions are important ingredients for the Point by Point (PbP) model calculation of multiplicity, spectra and other quantities related to the prompt neutron emission. For many fissioning systems experimental FF mass distributions are missing and in these cases an original procedure, exploiting available experimental FF charge distributions in the frame of PbP treatment, is proposed. Firstly this idea was successfully verified in the following cases: (i) for 239Pu( n th, f) because more experimental data sets concerning FF mass and total kinetic energy (TKE( A)) distributions are available making possible the use of the PbP model (as it was described in previous works devoted to other neutron-induced fission reactions) and also experimental charge distribution data of post-neutron FF exists; (ii) for the case of 234U fissioning nucleus because both types of experimental FF distributions are available, on one side FF mass and TKE( A) distributions measured for 233U( n th, f) and on other side FF charge and TKE( Z) distributions for 234U electromagnetic induced fission. In both cases mentioned above, the PbP model calculations of prompt neutron multiplicities, spectra and other quantities related to prompt neutron emission, obtained by using FF mass and charge distributions respectively, lead to very close results. Secondly the procedure was applied in the case of 232U( n, f) (for which experimental FF mass distributions are missing) by exploiting both types of experimental charge distributions: of post-neutron FF of 232U( n th, f) and of FF obtained for 233U electromagnetic induced fission. The obtained PbP model results of multiplicity, spectrum and other prompt neutron quantities are close to each other and in agreement with the predictions given by systematic trends. The proposed procedure is useful especially for fissioning actinides far from known and studied systems, giving reasonable predictions of quantities related to prompt neutron emission.