A Method for Controlling Scattered Radiation in Obtaining X-Ray Absorption Data by Photographic Means

Abstract

Errors caused by scattered radiation in photographic x‐ray absorption measurements can be materially reduced by (1) irradiating a minimum amount of matter, (2) placing the absorbing material some distance from the film, and (3) keeping the different filter elements separated by lead partitions so that scattering cannot spread indefinitely. These conditions have been met by the use of a lead chamber made up of several parallel longitudinal compartments. Filters differing in thickness are placed over holes in the end where the x‐rays enter and recording films are located at the exit end. This system has the further advantage that all filters are exposed simultaneously, thus promoting accuracy in relative absorption measurements, particularly when short exposure times only are possible. Experimental results show that, in a particular design, 97 percent of the scattering is eliminated.