Photonuclear Reactions: Systematical Disagreements, Methods of Overcoming Them, and Physical Consequences

There are many clear systematical disagreements, both in shape and magnitude, between data obtained in different experiments of decreased data accuracy and reliability. The systematical overview of photonuclear reaction cross-section values obtained at various experiments, first of all that from experiments with bremsstrahlung and quasimonoenergetic annihilation photons, has been carried out and used for discussion of the data's modern status. It was discovered that as a rule both total and partial photoneutron reaction cross sections obtained systematically differ from each other. Significant discrepancies between photonuclear-reaction cross sections obtained at various experiments were analyzed jointly. The disagreements of partial reaction cross-section data were interpreted as the result of a difference in neutron multiplicity sorting procedures used. A special method was used to make the data consistent. Joint analysis of the (γ,xn) (γ,n), and (γ,2n) reaction cross-section data obtained at both laboratories mentioned was carried out for nuclei 51V, 75As, 89Y, 90Zr, 115In, 116,117,118,120,124Sn, 127I, 133Cs, 159Tb, 165Ho, 181Ta, 197Au, 208Pb, 232Th, and 238U. Consistent data were evaluated. Some important physical consequences were pointed out