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无论对深入理解电子-原子的作用机制，还是在材料等领域的实际应用，电子轰击原子的内壳电离截面都具有重要意义。当前电子碰撞引起原子内壳电离的实验数据多集中在几十keV入射能量和中小Z靶原子，其它数据相对比较缺乏。本工作以能量为1.0 MeV电子轰击Ta和Au靶，通过测量靶原子特征X射线的产额，获得其K壳电离截面分别为13.3和10.1 b，L壳电离截面分别为554和338 b。并将实验结果和相应的理论进行了对比，结果显示，本实验测得的K壳电离截面与Casnati、Hombourger理论值、L壳电离截面与Scofield和Born-Bethe的理论值相符。“,”Accurate experimental data for atomic inner-shell ionization cross-sections by electrons are of basic importance both in understanding inelastic electron-atom interaction and its application. Up to now, most of available data on this process were mainly concentrated on the low and medium Z atoms by the bombardment of low energy electrons. In present experiments K-shell and L-shell ionization cross-sections of Ta and Au in collisions with 1.0 MeV eleltron were determined by measuring the characteristic X-rays emitted from the target atoms. For the present collision systems the K-shell ionization cross-sections were found to be 13.3 and 10.1 b, and the L-shell ionization cross sections were 554 and 338 b, respectively. The measured K-shell ionization cross sections are in reasonable agreement with the theoretic predictions of Casnati and Hombourger, while L-shell ionization cross sections are consistent with the theoretical results of Socfield and Born-Bethey.