Applications of new spectroscopic technique for the study of interactions of multiply-charged ions with gaseous targets in the extreme ultraviolet (EUV) region

A new optical device in the EUV spectral region based on glass capillary converter (GCC) has been developed for studies of fundamental collision process involving the Nevada multicharged ion ECR facility. This new unique device has been utilized in conjunction with a high resolution 2.2 m grazing incidence monochromator to record EUV spectra following Ar8++He and He2++He collisions. The authors have achieved a coefficient of intensity enhancement of radiation on the entrance slit of the monochromator ranging from 5-10 to 20-30, depending on the design of the gas cell. Concerning the Na and Mg-like structures observed by Bliman and coworkers, the authors have obtained a significant enhancement of intensity in the case of Ar8++He approximately by one order of magnitude. In addition, their spectra contain numerous new lines in the EUV region. Another striking result is the presence of the Lyman series in He II due to ionization excitation processes in the He target. This new spectroscopic method has huge potential for more detailed studies of collision processes with multicharged ions interacting with gaseous and surface targets not only in the EUV but also in the X-ray region