A High Intensity E.C.R. Stripped Ion Source

An ion source based on E.C.R. heating in a magnetic bottle works in our Laboratory since 1964. The characteristics of the plasma are: n = 1012 cm-3; w-> 1 keV ; W+ ~10 eV ; p > 10-5 torr. The microwave power P < 2 1KW at 10 GHz is coupled to the electrons either by a standing wave or a propagating wave. Our preliminary results with a 16 nA beam gave N+ = 44 %; N2+ = 36 % ; N3+ = 14 % ; N4+ = 4 % ; N5+ + N6++ N7+= 2 %. However due to the presence of H+2 the rate of N6+ and N7+ could not be measured correctly.