Scaling of SMP diode performance with geometry and voltage

The self-magnetic pinch (SMP) electron beam diode has been studied extensively as an intense, flash x-ray, radiographic source at Sandia National Laboratories. It has been fielded across a wide range of voltages and geometric configurations on the Radiographic Integrated Test Stand (RITS-6) inductive voltage adder accelerator and the Ursa Minor 21-cavity linear transformer driver accelerator. We present the observed scaling and reproducibility behavior of the SMP diode with variations in voltage and geometry, as well as effects of various materials used in the diode. With the proper configurations, we have observed excellent performance from the SMP diode at up to 8 MV with indications of improvement at even higher voltages. Proposed physical underpinnings of this behavior, based on measurements, analysis and numerical simulation, will be presented.