Source Plasma Study of the DuoPIGatron Ion Source for JT-60 Neutral Beam Injector

摘要

In an effort to develop a plasma source capable of producing a dense, uniform, and quiescent plasma for JT-60 neutral beam injectors, experimental studies on duoPIGatron ion sources have been pursued. In the 15 cm axisymmetric duoPIGatron ion source, the ion current density is about 250 mA/cm exp 2 , uniform to +-10% over the extraction grid. In the rectangular duoPIGatron source, the ion current is 190 mA/cm exp 2 , uniform to +-5% over the area of 8 cm by 24 cm. By measuring potential distributions of the source plasma, we have found the fact that copper buttons located at downstream of the intermediate electrode play an important role in raising the density level, gas efficiency, and arc efficiency as well as in improving the plasma uniformity. (Atomindex citation 11:500986)