Fermilab, Batavia, Illinois
If large enough the beam space charge strongly affects the beam stability in a circular accelerator. It results in a separation of coherent and incoherent tunes and, consequently, instability. Effects of space charge on the beam stability are considered in application to Fermilab Booster, Main injector and Recycler.
IUCF, Bloomington, Indiana
Fermilab, Batavia, Illinois
Scaling laws of the emittance growth factor (EGF) for a beam crossing the 6th order systematic space-charge resonances and the random 4th order resonance driven by octupoles are obtained by numerical multi-particle simulations. These scaling laws can be used in setting the minimum acceleration rate, and the maximum tolerable resonance strength for the design of non-scaling fixed-field alternating gradient (FFAG) accelerators.
Fermilab, Batavia, Illinois
The stable region of the Fermilab Booster beam in the complex coherent-tune-shift plane appears to have been shifted far away from the origin by its intense space charge making Landau damping appear impossible. However, it is shown that the bunching structure of the beam reduces this space-charge shift. As a result, the beam can be stabilized by suitable octupole driven tune spread.