The Effective U²³⁸ Resonance Capture Integrals of Uranium Metal and UO₂ Rods

The effective U²³⁸ resonance neutron capture integrals of uranium metal and UO₂ rods of a variety of diameters have been measured by an activation technique. Small corrections have been applied to compensate for departure of the flux spectrum from a 1/E shape. The results are compared with Hellstrand's measurements and with calculations by Nordheim. There is excellent agreement for UO₂. For U metal, agreement is not as good, but the difference is judged to be within the over-all uncertainty.