GENERATION OF SELF-PULSED MULTIPLY-CHARGED IONS BY AN XECL EXCIMER LASER

Multiple charge heavy ion pulses were extracted from a plasma produced by an XeCl excimer laser beam at a relatively low flux ( approximately 30 MW/cm2) focused on Si, Ge, Mg and Zn targets. An output peak current of Si3+ ions of 375 mA was recorded at an acceleration voltage of 200 V only. The insertion of a variable capacitance between the target holder and the acceleration electrode allows a self-bunching of the ion beam. When a W target was used, a higher incident laser flux ( approximately 90 MW/cm2) was necessary in order to produce ions from it.