Gettering experience in ISX or titanium is good for your health

Titanium gettering in the Impurity Study Experiment (ISX) vacuum vessel has allowed a significant improvement in the plasma parameters. For ohmic heating discharges, Zeff = 2.9→1.9, τE = 24→36 ms, and qψ = 3.4→2.8 ms. Most of the experiments have been carried out with titanium deposition only once or twice per day. Residual gas spectra taken between discharges show a return to the normal after only one or two plasma shots following gettering. A study of the parameters that reflect recycling and impurity content shows saturation after the first discharge following gettering. Nevertheless, the overall plasma behavior is affected by gettering for tens of discharges. Experiments continue in an attempt to evaluate more accurately the plasma effects of gettering.