thus serves as a simple catching device and can be pumped out by means of the pump 42 and processed again in all of the examples described above an additional amount of target material that is vaporized or sublimated due to the finite vapor pressure on the target path 22 from the inlet opening into the interaction chamber 4 to the interaction point 61 must be introduced for radiation generation in addition to the amount of target material that interacts directly with the energy beam 5 in order to generate a desired characteristic radiation in the plasma 6 this process of vaporization or sublimation is reinforced by the radiation from the plasma 6 that is absorbed by the target material therefore the effective loss of mass must either be compensated by a corresponding increase in the initial size of the individual targets 21 or u2014 as is shown in fig4 u2014 can be kept very small by means of one or more sacrifice targets 25 which serve as a vaporization shield 26 the solution to the vaporization problem according to fig4 can accordingly be combined with all other embodiment forms of the invention further as was mentioned with reference to fig4 target columns 24 with more than.