ACCELERATION OF 100 MA OF H- IN A SINGLE-CHANNEL ELECTROSTATIC QUADRUPOLE ACCELERATOR

Neutral beams for the next generation tokamaks will be based on multia mpere negative ion beams with a beam energy of about 1.0 MeV and pulse lengths of a thousand seconds. High intensity de beams at these level s of beam energy will require extensive development in electrostatic a ccelerators. At Lawrence Berkeley Laboratory, a two-module electrostat ic quadrupole (ESQ) accelerator was built to accelerate ions to 260 ke V. In this experiment, up to 100 mA of H- beam current was obtained fr om a Japan Atomic Energy Research Institute cesiated volume source usi ng a multiaperture preaccelerator which merged 19 beamlets into a sing le circular beam at the entrance to the BSQ accelerator. The H- beam w as accelerated by the ESQ to accelerate 200 keV without any significan t beam loss or emittance growth. (C) 1995 American Institute of Physic s.