200–1200 kV endpoint x-ray production using reflex triodes*

High-current (1-3 MA) reflex triodes are being developed as intense pulsed sources of moderate energy (200-1200 kV endpoint) bremsstrahlung. A triode consists of three coaxial electrodes: two cathodes and a flat anode foil between them. The grounded cathodes emit electrons that produce bremsstrahlung in the positive high voltage anode. The anode is made from thin tantalum to minimize attenuation of the low energy portion of the x-ray spectrum. The electrons must make many passes, or “reflex” through the foil for efficient x-ray production.