Microtron-based Compact, Portable Gamma-Ray Source

Battery-powered compact, portable sources of gamma rays with energies between 1 MeV and 6 MeV and with variable duty cycles are needed for a variety of applications, from homeland security to a broad range of industrial and medical applications. Radioactive sources, although compact, are not tunable and are hazardous even when not being used. Typical industrial electron accelerators that provide gamma rays of the required energy are not compact or portable, nor can they operate on batteries. We propose a novel temperature-stabilized solid-state permanent-magnet microtron electron accelerator to provide a lightweight gamma-ray source with outstanding performance parameters and flexibility. The electrons are accelerated by a small RF cavity powered by a highly-efficient magnetron power source. Compactness and portability are achieved by using a magnet that does not need coils, power, or cooling, and using an efficient accelerating system that minimizes the need for RF power and cooling. The classical microtron design that we propose has a built-in vacuum chamber that eliminates a reliability issue seen in betatron gamma ray sources. A prototype portable microtron will be produced in Phase II. In Phase I, computations and simulations will be done to demonstrate accelerator performance and to verify that all requirements can be met. In addition, a complete conceptual design of a prototype unit will be produced, including the electrical, electronic, mechanical, and magnetic components. The design will utilize commercially available components from the US. Commercial applications of compact gamma ray sources include detection of fissile materials, observation of flaws in industrial components, discovery of flaws and weaknesses in bridges and other construction structures, medical scanning, oil exploration and others.