大气压尖板电极结构重复频率纳秒脉冲放电中X射线辐射特性研究

X-ray generation in repetitive pulsed discharge in atmospheric air with a point-to-plane gap

文章通过碘化钠晶体和光电倍增管构成的X射线探测系统,研究了上升沿15 ns,脉宽30—40 ns量级,电压90 kV的大气压重频纳秒脉冲气体放电中X射线的辐射特性,X射线有效探测能量范围为10—130 keV结果表明放电产生的X射线主要集中在20—90 keV能量范围,而能量在十几keV的软X射线和超过90 keV的高能X射线数量很少.X射线辐射计数随脉冲重复频率的增加而增加,随着气隙距离的改变存在峰值,且峰值出现在弥散放电模式.

Research on the characteristics of X-ray emission in repetitive pulsed discharge is associated with the behavior of runaway electrons and the mechanism of nanosecond pulsed discharge.In the experiments,X-ray emission in the repetitive pulsed discharge with a rise time of～15 ns and an FWHM of 30-40 ns in atmospheric air is directly measured by a detection system consisting of NaI scintillator and a photomultiplier tube,and the energy range of the X-ray detector is demonstrated to be between 10 and 130 keV. Results show that main part of the energy of X-ray is from 20 keV to 90 keV,and a little X-ray with an energy of less than 20 keV or more than 90 keV is detected.X-ray emission increases with the increase of pulse repetition frequency,and it has a peak value with the variation of air gap spacing.There is a maximum value of X-ray emission when the nanosecond discharge appears in a diffuse mode.