Cross Sections of Partial Photoneutron Reactions: Problems of Reliability and New Data

• Published in: Moscow University physics bulletin Vol. 78; no. 3; pp. 291 - 302
• Main Authors: Davydov, A. I., Varlamov, V. V., Orlin, V. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.06.2023; Springer Nature B.V
• Subjects: Criteria; Cross-sections; Mathematical and Computational Physics; Neutron counters; Photon beams; Physics; Physics and Astronomy; Reliability; Theoretical; Uncertainty; data reliability; giant dipole resonance; absolute value; systematic uncertainties; cross sections of photoneutron reactions; data disagreement; new evaluated data
• ISSN: 0027-1349; 1934-8460
• DOI: 10.3103/S0027134923030062

The cross sections of partial photoneutron reactions , , and ( , 3 n ), the majority of which were obtained using beams of quasimonoenergetic annihilation photons, are discussed. Significant systematic uncertainties in the experimental results that far exceed the achieved statistical accuracy are analyzed. Using objective physical criteria for the reliability of partial reaction cross section data, experimental results for 50 nuclei ranging from V to Bi are examined. It is shown that in many cases, systematic uncertainties in experimental reaction cross sections are large, and these data do not meet physical criteria of data reliability. An experimental-theoretical method for evaluating reaction cross sections satisfying these criteria is described. The reasons for systematic uncertainties of several types are identified, which are due to both the limitations of the photoneutron multiplicity sorting method used in the experiments, and the peculiarities of the employed neutron detectors. New, reliable evaluated cross sections of partial reactions and the total photoneutron reaction are presented.