Abstract
The photoneutron thresholds for , , , , and were determined by measurement of the yield of activity as a function of the peak bremsstrahlung energy. Measurements of the photoneutron thresholds of , , and , which could be calculated accurately from the mass data, served to determine the energy scale. The photoneutron thresholds for and were found to be 10.61±0.05 Mev and 9.07±0.07 Mev, respectively.
The shape of the activation curves for , , and appeared to be a straight line for about 350 kev near threshold. The activation curves for and could be fitted accurately by functions of the form and , respectively, over a 3-Mev interval. refers to the peak x-ray energy and to the threshold energy.
- Received 6 August 1953
DOI:https://doi.org/10.1103/PhysRev.93.146
©1954 American Physical Society