Second harmonic x-ray irradiation from weakly ionized linear ferrum plasma

Abstract

In the plasma flash x-ray generator, a 200 nF condenser is charged up to 50 kV by a power supply, and flash x-rays are produced by the discharging. The x-ray tube is a demountable triode with a trigger electrode, and the turbomolecular pump evacuates air from the tube with a pressure of approximately 1 mPa. Target evaporation leads to the formation of weakly ionized linear plasma, consisting of ferrum ions and electrons, around the fine target, and intense K-series characteristic x-rays are produced from the plasma axial direction. At a charging voltage of 50 kV, the maximum tube voltage was almost equal to the charging voltage of the main condenser, and the peak current was about 15 kA. In the spectral measurement, Kβ rays were intense, and higher harmonic x-rays were observed. The pulse widths were 0.5 μs, and the maximum x-ray intensity was approximately 300 μGy.