Angular Distributions of (d,p) Reactions Using 14-Mev Deuterons

The angular distribution of ($d,p$) reactions for a series of target elements, using 14-Mev deuterons has been investigated. The targets chosen were thin foils of carbon, aluminum, nickel, silver, tantalum, gold, and bismuth. These were bombarded with deuterons from the MIT cyclotron in the center of a large scattering chamber shielded from the cyclotron by 4 ft of concrete. The emitted protons were detected in a triple proportional counter which could be set at any angle from 15° to 135° to the beam. In all cases the measured intensity of protons per unit solid angle is found to be greater in the forward direction. The ratio of the area under the distributions from 20° to 90° to that between 90° and 140° varies from 1.6 to 13. For a given element this ratio increases with proton energy. In addition, for carbon and aluminum, in which individual groups can be resolved, the intensity of protons in a given group, in some cases, exhibits maxima at various angles. In the three elements of highest atomic number the intensity rises from back angles to a maximum at some forward angle and then drops off towards zero degrees. The position of this "turn over" angle appears to increase slowly with atomic number. The general features of the distributions appear to be explainable on a stripping picture rather than that of a compound nucleus.