1975/03/01 by G.J. Kirouac, H.M. Eiland · 1 voice
Engineering · Physics and Astronomy · #Nuclear Physics and Applications #Nuclear physics research studies #Nuclear reactor physics and engineering
paper · doi:10.1103/physrevc.11.895
openalex publication_date 1975/03/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/07
The energy dependent total neutron cross section of 151Sm, a fission product poison, has been measured from thermal neutron energies up to about 2.3 keV. The results obtained for the thermal (0.0253 eV) cross section, resonance integral, s-wave level spacing, and strength function were: 15 200 \ifmmode±\else\textpm\fi 300 b, 3520 \ifmmode±\else\textpm\fi 160 b, 1.72 \ifmmode±\else\textpm\fi 0.07 eV, and S0=3.65\ifmmode±\else\textpm\fi0.48\ifmmode×\else\texttimes\fi10^\ensuremath-4, respectively. The neutron widths for 120 resonances up to 300 eV were obtained by conventional analytic methods and the radiation widths were also obtained for 13 low energy resonances. The strength function was derived from resolved neutron resonances and from the average keV cross section. In addition, the Dyson-Mehta \ensuremathΔ3 statistic was calculated from the level sequences of Sm isotopes and compared with the prediction of the statistical orthogonal ensemble. The level densities of six Sm isotopes and seven Nd isotopes were used to compute the Fermi level density parameter a, and these results are discussed in light of the nuclear structure. Finally, the systematic behavior of s-wave strength functions in the 142\ensuremath≤A\ensuremath≤158 mass region is examined.NUCLEAR REACTIONS 151Sm(n, n), (n, \ensuremathγ), E=0\ensuremath-2.5 keV; measured \ensuremathσt(E); deduced E0, g\ensuremathΓn, \ensuremathΓ_\ensuremathγ, S0, 〈D0〉; O.E. theory test; studied systematics S0, 〈D0〉 for 142\ensuremath≤A\ensuremath≤158.