Design and Fabrication of the BNL Radio Frequency Quadrupole

The Brookhaven National Laboratory polarized H- injection program for the AGS will utilize a Radio Frequency Quadrupole for acceleration between the polarized source and the Alvarez Linac. Although operation will commence with a few ¿ amperes of H- current, it is anticipated that future polarized H- sources will have a considerably improved output. The RFQ will operate at 201.25 MHz and will be capable of handling a beam current of 0.02 amperes with a duty cycle of 0.25%. The resulting low average power has allowed novel solutions to the problems of vane alignment, rf current contacts, and removal of heat from the vanes. The cavity design philosophy will be discussed together with the thermodynamics of heat removal from the vane. Details of the fabrication will be presented with a status report.