Electron impact broadening of multicharged ion lines of astrophysical interest: Ne VII, Ne VIII and Si XI

The modified semi-empirical method, often used in the investigations of stellar plasma for the determination of needed Stark line widths, is adapted here to use more accurate collision strengths instead of Gaunt factor. It is demonstrated that in such a way its applicability is extended to highly charged ions and good agreement is obtained with the more sophisticated semi-classical perturbation approach up to Si XI. Using this method, Stark line widths of several complex ions: two Be-like ions (Ne VII and Si XI) and one Li-like neon (Ne VIII) were calculated. The obtained results were compared with experiments and other theoretical approaches. (c) 2006 Elsevier B.V. All rights reserved.