Experimental study of interactions of highly charged ions with atoms at keV energies. Progress report, May 15, 1981-May 14, 1982

An electron beam ion source, EBIS, to be used in experimental investigations of interactions of highly charged ions with atoms at keV energies has been constructed. The EBIS generates low energy, multiply charged ions by successive electron impact ionization of ions trapped in an intense, magnetically confined electron beam. A 2 keV, approx. 10 A/cm2 electron beam has been successfully launched from an external, high convergence electron gun into a 4 kG, 50 cm long solenoidal magnetic field and propagated through sixteen tubes fabricated from stainless steel mesh and concentric with the beam. An innovative feature of the source is the use of a distributed sputter-ion pump to create the necessary ultra-high vacuum environment in the ionization region. A microprocessor based sixteen channel power supply which generates the potential distribution applied to the drift tubes for axial trapping of the ions has been designed and constructed. A study of source properties is in progress