Investigation of the 56Fe(n, γ)57Fe and 58Fe(n, γ)59Fe reactions

doi:10.1016/0375-9474(80)90400-5

Nuclear Physics A

Volume 344, Issue 3, 11 August 1980, Pages 421-445

https://doi.org/10.1016/0375-9474(80)90400-5 Get rights and content

Abstract

The γ-radiation has been investigated produced by thermal neutron capture in a natural Fe sample and in a sample enriched in ⁵⁸Fe. Of the 253 γ-rays ascribed to the ⁵⁶Fe(n, γ)⁵⁷Fe reaction, 191 have been placed in the ⁵⁷Fe level scheme (of which 124 placements are new); of the 138 γ-rays observed in the ⁵⁸Fe(n, γ)⁵⁹Fe reaction 68 have been placed (with 55 new placements). Excitation energies (with 0.02–0.7 keV error) and branching ratios have been determined of 60 bound levels in ⁵⁷Fe and of 27 in ⁵⁹Fe. The Q-values of the ^{56, 58}Fe(n, γ) reactions amount to 7646.0 ± 0.2 and 6581.0 ± 0.2 keV, respectively. One can conclude that $J = 32$ for the 2836 keV level in ⁵⁷Fe, and that $J^{π} = 32^{−}$ for the 2570, 3072, 3104, 3160 and 3384 keV levels in ⁵⁹Fe.

A shell-model calculation has been performed with up to two holes in the $1 f_{72}$ sub-shell and particles in the $2 p_{32}$ , $1 f_{52}$ and $2 p_{12}$ sub-shells. The energies of low-lying ^{57, 58,59} reproduced with a mean deviation of 0.17 MeV. The surface-delta interaction appears superior over the Kuo-Brown interaction in explaining the electromagnetic properties of the lowest six states of ⁵⁷Fe.

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Investigation of the 56Fe(n, γ)57Fe and 58Fe(n, γ)59Fe reactions

Abstract

Nucl. Data Sheets

Nucl. Data Sheets

Nucl. Data

Nucl. Instr.

Jülien Report Jül.-1087-Rx

Phys. Rev.

Nucl. Phys.

Netherlands Energy Research Foundation Report RCN-75-004

Nucl. Phys.

Phys. Rev.

Nucl. Phys.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

Phys. Lett.

Z. Phys.

Nucl. Data Sheets

Can. J. Phys.

Investigation of the ⁵⁶Fe(n, γ)⁵⁷Fe and 58Fe(n, γ)⁵⁹Fe reactions