The angular distribution of alpha-particles from proton bombardment of lithium has been measured with an ionization chamber and linear amplifier at proton energies of 1.0 to 3.0 Mev. The yield as a function of angle in the center-of-mass system follows the form $Y\left(\theta \right)=Y\left(90\mathrm{}°\right)\times (1+A {cos}^2\theta +B {cos}^4\theta )$, where the term in ${cos}^4\theta$ is clearly present. The value of $A$ shows a resonance peak at about 1 Mev and declines to a low value at 3 Mev. Values of $B$ calculated from the data range from -0.1 to -1.2 but are not sufficiently well resolved to determine their dependence upon bombarding energy.

• Received 27 October 1947

DOI:https://doi.org/10.1103/PhysRev.73.241