Linac Alignnent Techniques

Techniques of aligning linear accelerators are discussed with specific reference to the alignment system of the two-mile accelerator. This system uses a "three-point" method by which a point which is to be aligned is brought into coincidence with the line as defined by its end points. The end points are a laser and a photo-electric detector. A rectangular Fresnel lens is located at each point to be aligned to define the "third point."