Performance of the ASDEX neutral beam injector

The first of two neutral beam injectors for the ASDEX tokamak has been put into operation. The design value of 1.25 mw neutral power into ASDEX was obtained within a few weeks of operation; the injection system was found to work quite reliably. Beam power mesurements have shown a transmission of total power to the beamline calorimeter of 70%, a neutralization efficiency of 60 %, reionization losses between magnet and torus of less than 10 %, and geometric losses within the duct of a few percent, resulting in a neutral power offered to the plasma between 35 % and 40 % of the drain power. Measurements have been performed concerning the properties of the Ti-evaporator pumping system. The results are compared with beamline code calculations