Intense nickel-K-photon irradiation from weakly-ionized linear plasma x-ray source with a zinc reflector

The linear-plasma flash X-ray generator consists of a high-voltage power supply, a 200-nF high-voltage condenser, a turbomolecular pump, a trigger-pulse generator, and a demountable flash X-ray tube. In the flash X-ray generator, the condenser is charged up to 50 kV by the power supply, and flash X-rays are then produced by the vacuum discharging. The X-ray tube is a demountable triode with a rod-shaped nickel (Ni) target, a zinc (Zn) reflector and a trigger electrode, and the turbomolecular pump evacuates air from the tube at a pressure of approximately 1 mPa. The Ni-target evaporation leads to the formation of weakly ionized linear plasma, consisting of Ni ions and electrons, around the target. In the plasma, K-series characteristic X-ray photons (K photons) are produced, and bremsstrahlung photons with energies beyond the Ni-K-edge energy are absorbed by the plasma and converted into Ni-K photons. Subsequently, Zn-K photons from the Zn reflector are absorbed by the linear Ni plasma and converted into Ni-K photons. Thus, intense Ni-K photons (rays) are irradiated from the plasma axial direction by K-ray amplification by spontaneous emission of radiation (KASER).