Sato Eiichi, Tanaka Etsuro, Mori Hidezo, Kawai Toshiaki, Ichimaru Toshio, Sato Shigehiro, Takayama Kazuyoshi, Ido Hideaki
Department of Physics, Iwate Medical University, Morioka 020-0015, Japan.
Med Phys. 2005 Jan;32(1):49-54. doi: 10.1118/1.1829247.
The high-voltage condensers in a polarity-inversion two-stage Marx surge generator are charged from -50 to -70 kV by a power supply, and the electric charges in the condensers are discharged to an x-ray tube after closing gap switches in the surge generator with a trigger device. The x-ray tube is a demountable diode, and the turbo molecular pump evacuates air from the tube with a pressure of approximately 1 mPa. Clean molybdenum Kalpha lines are produced using a 20 microm-thick zirconium filter, since the tube utilizes a disk cathode and a rod target, and bremsstrahlung rays are not emitted in the opposite direction to that of electron acceleration. At a charging voltage of -70 kV, the instantaneous tube voltage and current were 120 kV and 1.0 kA, respectively. The x-ray pulse widths were approximately 70 ns, and the generator produced instantaneous number of Kalpha photons was approximately 3 x 10(7) photons/cm2 per pulse at 0.5 m from the source of 3.0 mm in diameter.
在极性反转两级马克思脉冲发生器中的高压电容器由电源充电至-50至-70 kV，在脉冲发生器中使用触发装置闭合间隙开关后，电容器中的电荷被释放到X射线管。X射线管是可拆卸二极管，涡轮分子泵将管内空气抽至约1 mPa的压力。使用20微米厚的锆过滤器产生纯净的钼Kα线，因为该管采用盘形阴极和棒状靶，且不会在与电子加速相反的方向发射轫致辐射。在充电电压为-70 kV时，瞬时管电压和电流分别为120 kV和1.0 kA。X射线脉冲宽度约为70 ns，在距直径3.0 mm的源0.5 m处，该发生器每脉冲产生的Kα光子瞬时数量约为3×10(7)个光子/cm2。
