Formation and Acceleration of Nanosecond Beam Pulses in an Isochronous Cyclotron

Use of cyclotron beams for time-of-flight experiments requires the production of high-intensity ion bursts of very short time duration. A lower limit for obtaining short pulses of a defined energy spread is set by the intrinsic energy-time spread of the ion beam. The factors determining this spread are investigated. Central-region design features facilitating the formation of nanosecond pulses in the NRDL cyclotron are discussed, and results of detailed calculations on the magnitude of the intrinsic energy-time spread are presented.