Similarities and Differences in Processes of 58,60Ni Photodisintegration

• Published in: Bulletin of the Russian Academy of Sciences. Physics Vol. 87; no. 8; pp. 1179 - 1187
• Main Authors: Varlamov, V. V., Davydov, A. I., Orlin, V. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.08.2023; Springer Nature B.V
• Subjects: Bremsstrahlung; Criteria; Cross-sections; Hadrons; Heavy Ions; Isotopes; Nuclear Physics; Nuclei; Photodisintegration; Physics; Physics and Astronomy; Reliability; Shells (structural forms)
• ISSN: 1062-8738; 1934-9432
• DOI: 10.3103/S1062873823703070

The reliability of cross sections of the (γ, 1 n ) and (γ, 2 n ) photoneutron partial reactions for 58,60 Ni nuclei obtained in experiments performed on beams of bremsstrahlung and quasi-monoenergetic annihilation photons is investigated using objective physical criteria. It is found that data of the first type of experiment do not satisfy those criteria and definitely are not reliable. At the same time, there are serious doubts about the reliability of data obtained in the second type of experiment. New cross sections of partial reactions on 58,60 Ni nuclei that satisfy physical criteria of reliability are used to analyze characteristics of photodisintegration processes for both isotopes. It is found there are coniderable discrepancies between evaluated and experimental cross sections of different reactions for neighboring Ni nuclei (differing by two neutrons) because of various types of systematic uncertainties of very different characters for 58 Ni and 60 Ni isotopes. It is shown this is due not only to differences between energy thresholds and absolute values of cross sections of reactions (γ, 1 n 1 p ) and (γ, 2 n ) but to major differences between characteristics of the shell structure in neighboring isotopes as well.