Inverse problem in the thick-target method of measurements of inner-shell ionization cross sections by electron or positron impact

Abstract

In this paper, the Tikhonov regularization method and the classical molecular dynamics method are used to deal with the inverse problem involved in the measurement of inner-shell ionization cross sections by using the thick-target method. These two methods are applied to simulated and real experimental data for the $K$-shell ionization of a Ni element by electron impact. The satisfactory results can be obtained by using these two methods to treat the inverse problem involved in the thick-target method. The estimated total error for the method described in this paper is about 10%, which is the same order as the experimental error with the thin-target method. It can be concluded that the thick-target method can be reliably used in the future for the measurement of inner-shell ionization cross sections by electron or positron impact near the threshold energy region.