Neutron resonance spectroscopy. XIII. Na to 320 keV

Results are presented of measurements of the total cross section vs energy which was measured to 320 keV for pure metallic sodium. R-matrix fits were made to the seven prominent observed resonances. The best-fit parameters for (E₀,Γ,J,l) for each resonance are: (2.850, 0.400, 1, 0); (53.15, 1.08, 2, 1); (199.0, 4.5, 1, 0); (212.5, 15, 0, 1); (238, 3.9, 2, 1); (242, 3.5, 0, 1); (297, 1.8, 2, 0), where E₀ and Γ are in keV. Three levels are assigned to be s levels, and four to be p levels. This gives ${10}^4{S}_0=0.24\left(1_{-0.58}^{+1.91}\right)$ and ${10}^4{S}_1=2.06\left(1_{-0.39}^{+0.77}\right)$. The S₁ evaluation includes the presence of weak p levels seen in capture measurements by others.