Status of the AGS polarized negative ion source

A polarized negative ion source (H) has been modified for use in the A Anating Gradient Synchrotron to produce once every second a beam of 7.5 mic roamperes in .5 ms pulses. The source was based on the co−linear colliding principle whereby a polarized thermal atomic hydrogen beam collides in the interaction (solenoid) region with 40 keV neutral cesium particles, producing the negative hydrogen ions by charge exchange processes.(AIP)