Radiographic performance of Cygnus 1 and the Febetron 705

Spot sizes are measured for medium energy X-ray generators. The Cygnus X-ray source [J. R. Smith et al., 2002] is developed for support of the Sub-Critical Experiments Program at the Nevada Test Site. Cygnus uses proven pulsed power technology to drive a rod pinch diode at 2.25 megavolts. Four rads at one meter is achieved in a 50-ns FWHM pulse and the radiographic spot size is as small as 1 mm-diameter. Radiographic spot size is measured employing roll bars and resolution targets. Images are recorded on film and storage phosphor, digitized, and analyzed. The Febetron 705 X-ray source operates at 2.3 megavolts and is rated at 500 millirads at one meter. A demountable diode tube provides the ability to replace the standard diode with custom hardware. Spot sizes for standard hardware are measured. New diode designs are investigated in an effort to generate smaller radiographic spot sizes to produce improved radiographic images.