The ${\mathrm{O}}^{16}(\gamma ,n){\mathrm{O}}^{15}$ cross section has been measured using least-structure analysis of photonuclear yield functions for energy to 65 MeV. In the giant-resonance energy region considerable structure is reported, in good agreement with structure reported using other methods. The resolution of the least-structure method is comparable to resolution obtained by other methods, and in certain energy regions is superior. The cross section extends to energy above the giant resonance, exhibiting prominent structure to the highest energy measured. Absolute cross sections are reported in good agreement with values obtained elsewhere from yield functions, but approximately 20% higher than measurements made using monochromatic photons.

• Received 13 May 1965

DOI:https://doi.org/10.1103/PhysRev.143.712