Abstract
The parameters a and δeff appearing in the back-shifted Fermi gas model are determined for about 3000 nuclei on the basis of modern estimated experimental data and the proposed systematics. For 272 of these nuclei, the parameters are deduced from experimental data on the cumulative numbers of low-lying levels and on mean spacings between S-wave neutron resonances at the neutron binding energy in the nuclei. For 952 nuclei, the parameter δeff is calculated by using the cumulative numbers of low-lying levels and values of the parameter a that were obtained via an interpolation from the points corresponding to the aforementioned 272 nuclei. For the remaining nuclei, the parameters a and δeff are obtained on the basis of the proposed systematics. An expression is constructed for taking into account the damping of shell effects with increasing excitation energy of nuclei. The results are compared with those from other studies.
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References
A. Gilbert and A. G. W. Cameron, Can. J. Phys. 43, 1446 (1965).
H. K. Vonach and J. K. Huizenga, Phys. Rev. 138, 1372 (1965).
A. V. Malyshev, Level Density and Nuclear Structure (Atomizdat, Moscow, 1965).
W. Dilg, W. Schantl, H. Vonach, and M. Uhl, Nucl. Phys. A 217, 269 (1973).
A. V. Ignatyuk, Statistical Properties of Excited Nuclei (Énergoatomizdat, Moscow, 1983).
Huang Zhongfu, He Ping, Su Zongdi, and Zhou Chunmey, Chin. J. Nucl. Phys. 13, 147 (1991).
Handbook for Calculations of Nuclear Reaction Data, Report IAEA-TECDOC-1034 (International Atomic Energy Agency, Vienna, 1998).
A. V. Ignatyuk, G. N. Smirenkin, and A. S. Tishin, Yad. Fiz. 21, 485 (1975) [Sov. J. Nucl. Phys. 21, 255 (1975)].
A. V. Ignatyuk, K. K. Istekov, and G. N. Smirenkin, Yad. Fiz. 29, 875 (1979) [Sov. J. Nucl. Phys. 29, 450 (1979)].
V. S. Ramamurthy, S. K. Kataria, and S. S. Kapoor, in Proceedings of IAEA Advisory Group Meeting on Basic and Applied Problems of Nuclear Level Densities, New York, Report BNL-NCS-51694 (Brookhaven National Laboratory, Upton, NY, 1983).
K. H. Schmidt, H. Delagrange, J. P. Dufour, et al., Z. Phys. A 308, 215 (1982).
A. V. Ignatyuk, V. S. Stavinskii, and Yu. N. Shubin, in Proceedings of Second International Conference on Nuclear Data for Reactors (IAEA, 1970), p. 885.
V. M. Bychkov, O. T. Grudzevich, and V. I. Plyaskin, Vopr. At. Nauki Tekh., Ser. Yad. Konstanty, No. 3, 14 (1987).
A. A. Katsanos, R. W. Show, Jr., R. Vandenbosch, et al., Phys. Rev. C 1, 594 (1970).
D. Kopsch and S. Cierjaks, in Statistical Properties of Nuclei (Plenum, New York, 1972), p. 455.
J. K. Huizenga et al., Phys. Rev. 182, 1149 (1969).
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Translated from Yadernaya Fizika, Vol. 63, No. 5, 2000, pp. 821–827.
Original Russian Text Copyright © 2000 by Plyaskin, Kosilov.
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Plyaskin, V.I., Kosilov, R.A. Level-density parameters in the back-shifted Fermi gas model. Phys. Atom. Nuclei 63, 752–757 (2000). https://doi.org/10.1134/1.855702
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DOI: https://doi.org/10.1134/1.855702