A scheme for the accumulation of current in ISABELLE is pro¬posed. 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 pseudo-adiabatically 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 re-bunched 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 sig¬nificant 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 longi¬tudinal characteristics arise. It is concluded, however, that using the scheme suggested, (1) the transverse density required to attain a high luminosity in ISABELLE can be reached and (2) the longitudinal characteristics called for can also be obtained in the sense that the high frequency impedance limit for avoiding longitudinal instability in the stacking ring and especially in the large circumference ISA ring is comfortably high. Although the design procedure is given in general terms, sample computa-tions appropriate for ISABELLE are performed.
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