Angular Distributions of 22-Mev Protons Elastically Scattered by Various Elements

Angular distributions of 22-Mev protons elastically scattered by fifteen elements from beryllium to thorium were measured with the internal, circulating beam of the Oak Ridge National Laboratory 86-inch cyclotron. The experimental methods, which are somewhat unconventional, are described. The results show all the characteristics of diffraction scattering including at least two maxima and minima for each element. The angles at which these occur can be traced from element to element through the periodic table, following a $\frac{\ensuremath{\lambda}}{R}$ dependence with fairly good accuracy.