Induction acceleration scenario from an extremely low energy in the KEK all-ion accelerator

Direct injection of fully stripped carbon ions into a fast-cycling induction synchrotron and their capture by the barrier bucket

“…A better vacuum is planned for the KEK-DA, where all outgassing accelerator components responsible for degrading the vacuum, such as the extraction kickers, will be removed from the beam line. Furthermore, the induction acceleration system will be improved by introducing a variable dc power supply, without which the KEK-DA has had to accelerate heavy ions discretely with pulse-density control [14], inducing beam centroid oscillation with a large amplitude due to synchrobeta coupling, which results in emittance blowup [2].…”

“…The injected ion bunch is trapped by a pair of barrier voltage pulses that are output in the induction cells. Two-turn induction cells, in which the magnetic core is wound with two bare coppercoil turns, are used [14]. The induction cells are energized by the switching power supply only for generating the barrier bucket at the same timing every turn, because acceleration is not carried out.…”

The KEK Digital Accelerator and Its Brothers

“…It is worth emphasizing that an amplitude of the required acceleration voltage has to vary in time through the entire acceleration period in the form of Vreq(t)=C0dB(t)/dt, where  is the bending radius and C0 is the circumference, and B(t) is the guiding magnetic flux density. To meet this requirement, density control of the acceleration voltage pulse has been employed [13]. The injected beam is captured with a pair of barrier voltage pulses and accelerated with other pulse voltages generated in the different induction cells.…”

Induction acceleration of heavy ions in the KEK digital accelerator: Demonstration of a fast-cycling induction synchrotron

“…4. To meet the requirements of the induction acceleration system, the following scenarios for pulse voltage generation were developed [13] and demonstrated:…”