Scheme for current accumulation in ISABELLE using a low energy stacking ring

A scheme for the accumulation of current in ISABELLE is proposed. The steps in the procedure are as follows: (1) The 200-MeV linac at BNL would operate with a short pulse. One turn would be injected into the AGS, accomplished with a fast kicker in the AGS appropriate for the deflection of the 200 MeV beam. (2) The single turn pulse would be captured pseudoadiabatically and then accelerated. The resulting 12 bunches would be extracted at 29.4 GeV. A fast kicker rising between bunches would be used for this purpose. (3) The bunches would be matched and synchronously transferred to the stacking ring (SR) where sufficient current would be accumulated by the phase displacement technique used at the ISR. (4) The intense coasting beam in the SR would be rebunched into a single bunch and transferred to ISABELLE. The same fast kicker could be used for both injection into and ejection out of the SR. (5) A few such bunches would be stacked azimuthally in the ISA to achieve the final ISABELLE current. The details of the procedure are discussed, emphasizing the critical factors and significant parameters at each step. The key focal points are at 200 MeV where a space charge limitation on betatron density is encountered and at 29.4 GeV where limitations on the beam's longitudinal characteristics arise. The design procedure is given in general terms, and sample computations appropriate for ISABELLE are performed. (auth)