Proton Channeling in Fluorite-Type Single Crystals

In order to study the proton channeling process in the single crystals of CaF 2 and BaF 2 the half-angles and minimum yields for axes and planes were measured by means of Rutherford backscattering in the energy range 0.60-1.20 MeV and of gamma rays from the 873 keV resonance in the 19 F(p,αγ) 16 O reaction. The parameter dependence of the half-angles observed for the axes (<111>, <110>, and <100>) is dependent on the target crystals, and that for the planes ({110} and {112}) depends on the Miller index of planes. if the effects of thermal vibration and planar spacing are taken into account on the basis of Barrett's calculations, the parameter dependence and magnitudes of the measured half-angles show reasonable agreement with the calculations. The minimum yields for the mixed and monatomic rows along the axes agree reasonably with the predicted values; however, the minimum yields for the planes are considerably larger than those predicted.