Centrifugal space-charge force for bunched beams

摘要

In 1990, E. Lee showed for a DC beam that the effect of the centrifugal space-charge force (CSCF) on an electron's transverse motion in a end is cancelled to lowest order by the effect of the potential depression of the beam. However, this cancellation does not in general occur when the beam is bunched. We solve for the harmonic scalar and vector potentials and explicitly find the energy-independent transverse and longitudinal space-charge forces. We make estimates of the emittance growth as a function of bend angle and path length resulting from these forces.