Multi-sample negative ion source

A cesium sputter, negative ion source was developed and built at Triumf. While designed for accelerator mass spectrometry, it can be applied in any field requiring intensive negative ion beams covering the whole range from hydrogen to uranium. The source features an internal cesium oven and simplified target insulation. A pneumatically actuated target changer contains a 28-sample wheel but allows manual placing of single samples as well. In initial runs the source produced over 1 mu A of (CaH3-)-Ca-40 and .25 mu A of Al-27(-) beams. The construction of the source and the operation of the sample changer are discussed in this article. (C) 1996 American Institute of Physics.