Electron impact excitation of Ge-like to Cu-like xenon ions in the extreme ultraviolet

Abstract

Electron impact excitation of Ge-like (Xe22+) to Cu-like (Xe25+) highly charged xenon ions are studied and dipole allowed fine-structure transitions in the wavelength range 9–25 nm are considered. We use relativistic distorted wave method to calculate the electron excitation cross sections for the different transitions of the four ions in the scattered electron energy range from excitation threshold to 1500 eV. The ionic bound state wavefunctions have been obtained using multi-configuration Dirac–Fock method. To ascertain the accuracy of the wavefunctions, the wavelengths and oscillator strengths of the considered transitions in these ions are calculated and compared with the previously reported measurements and other theoretical calculations, where available. For plasma diagnostic applications, the obtained cross sections are further used to calculate the rate coefficients of the transitions as well as fitted with an analytical expression which can be used in plasma model conveniently.

Electron Impact Excitation of Extreme Ultra-Violet Transitions in Xe7–Xe10 Ions

“…In order to clearly demonstrate this trend, Figure 2 displays rate coefficients for the transitions reported in Table 7 for Xe 8+ . The same behaviour has been noticed in our previous work on excitation of highly charged xenon ions [25].…”

“…This ensures the quality of the target ion's wavefunctions that are crucial in determining the accuracy of the scattering parameters. Moreover, the RDW method has been successfully implemented in the previous work on a variety of targets from closed to open-shell systems and neutral atoms to multiply or highly charged ions atoms/ions [25][26][27][28][29][30]. It has also been found that using RDW cross sections in a collisional radiative (CR) model provides plasma parameters that are in better agreement with the measurements [31][32][33][34].…”

Study of Electron Impact Excitation of Na-like Kr Ion for Impurity Seeding Experiment in Large Helical Device

“…To appropriately integrate the electron impact excitation process into a suitable plasma model, the necessary excitation rate coefficients can be derived using the computed EIE cross-sections and calculated using the following expression [40,42]:…”