X- and gamma -rays computerized minitomograph scanner for soil science

A computerized tomograph scanner system that uses X- and gamma -rays for applications in soil science is described. Use of the apparatus in measuring volumetric water content to an accuracy of +or-3% and soil bulk density to +or-2% (in grams per cubic centimeters) is discussed. The system features translation and rotation scanning modes, a 200-mm effective field of view, signal processing by pulse counting, and 1.0-mm spatial resolution. The system's advantages over classical methods are listed, principles of the tomographic method and physical considerations are presented, and the system's design is described. >