Ion source developments for the Relativistic Heavy Ion Collider

Abstract

When the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is completed in 1999, the Tandem Van de Graaff, using cesium sputter sources, will produce the gold ions. The sputter sources are operated in a unique pulsed beam mode that allows the injection into the tandem of 200 to 300 μAmps of negative ions for up to 2 msec. This is several orders of magnitude higher instantaneous current than is possible in the direct current mode. These high current pulses have severe problems with space charge forces. The research to overcome the space charge forces has resulted in a 500 μsec pulse containing 9×109 ions after acceleration in the tandem. This a three fold increase in intensity in the last three years. There is also growing interest in other ion species specifically iron, silicon, and uranium. The research to produce useable quantities of these ions is also presented.