Collision Cross Sections for D — D Neutrons

The nuclear collision cross sections of 22 elements for the neutrons from a deuteron-deuteron source have been measured. The geometrical arrangement of the experiment was such that only small corrections to the measured transmission were necessary. The neutron energy was 2.88±0.04 Mev. The cross sections are found to vary irregularly with the atomic weight. The proton cross section determined for both paraffin and water scatterers is found to be 2.36×${10}^{-24\mathrm{}}$ ${\mathrm{cm}}^2$, which is smaller than the value predicted by theory. In addition, the cross sections of a number of elements for neutrons of 2.46 Mev energy have been measured. For some elements the cross section is found to increase with an increase in neutron energy, for others it decreases.