Parameters of the best approximation for distribution of the reduced neutron widths. The most probable density of neutron resonances in actinides

Abstract: In the frameworks of hypothesis of practical constancy of the neutron resonance number in small fixed intervals of neutron energy, their most probable value was determined for nucleus mass region 230<A<244 from approximation of the reduced neutron widths by superposition of two or four independent distributions. This was done under assumption that a set of the measured neutron amplitudes can correspond to one or to superposition of some normal distributions with non-zero average and dispersion differing from reduced neutron width. The main result of the analysis: the mean spacing and neutron strength function values can be determined only with unknown systematical uncertainty whose magnitude is determined by unknown precision of the Porter-Thomas hypothesis correspondence to concrete experimental sets of resonances and unknown experimental mean neutron widths.