Study Of The Measurement Of Atomic Inner-Shell Ionization Cross-sections By Electron Impact

The study of atomic inner-shell ionization cross-sections by low-energy electron impact is significant in both theoretical researches and practical applications. On the one hand, the theoretical validity needs to be tested by a large number of experimental data. On the other hand, accurate experimental data are required in many high-technology fields, such as in plasma physics, astrophysics, etc. However, so far, only a few experimental investigations have been carried out to measure L and M-shell electron impact ionization cross-sections. They mainly concentrate on K-shell ionization cross-sections. Moreover, it is also found that significant discrepancies exist between available data from different authors. Therefore, it is necessary to acquire more accurate data by improving experimental technique and data processing method.In this paper, possible factors, which affect the experimental accuracy, are studied. These factors include:(1) The top aperture and side aperture of the Faraday cup for collecting incident electrons can cause electron escape. It is difficult to evaluate the electron escape ratio by the general methods. In this paper, the problem was solved by Monte Carlo computer code PENELOPE. When using Monte Carlo simulation, a file describing the geometric characteristic of the Faraday cup must be created first. By simulating a great deal of electrons' transportation in the Faraday cup, a conclusion that the electron escape ratio is below 0.3% was obtained.(2) The detection efficiency calibration of Si(Li) detector in low-energy region down...