Angular correlation studies of thin metal films

Angular correlation of positron annihilation radiation is widely used in solid state physics studies (Goldanskii; Hautojärvi), in the defectoscopy of monocrystals in particular (Nielsen et al.). The interest to surface studies gave rise recently to very sophysticated and expensive method of positron beams (Goldanskii et al.). The recent study and recently published papers (Aravin et al.; Valiev et al.) demonstrate, however, that valuable information on surface properties can be obtained using the traditional angular correlation (AC) technique. [Russian Text Ignore]