The booster-to-AGS beam transfer fast kicker modulators

The authors describe modulator developments for the Brookhaven booster extraction and the Alternating Gradient Synchrotron (AGS) injection fast kickers. To achieve the design specifications, an extensive development effort has been pursued, including distributed parameter estimation and measurement, computer aided analysis and design, pulse shaping and tail-biting circuit test, prototype construction, etc. The test results are presented. The modulators are projected for both proton and heavy ion operation. The equivalent load inductance is about 2.1 to 2.3 mu H for each modulator. The pulse-forming network (PFN) voltage is required to be below 40 kV for operation in air. The rise time of the pulse for proton beam transfer is 120 ns up to 97% of full current (1000A), and for heavy ion beam transfer, the requirement is 160 ns up to 98% of full current (1615 A). During the fourth batch transfer of the proton beam from the booster to the AGS, the pulse fall time of the AGS injection fast kicker has to be very fast (<140 ns), so that it does not appreciably deflect the first batch of injected protons that is circulating in the AGS.<>