Peak current reduction in presence of RF phase modulation in the dual RF system

High harmonic cavities are widely used in electron storage rings to lengthen the bunch, thereby enhancing the Touschek lifetime, reducing the IBS effect, as well as providing Landau damping. When the RF phase is modulated in such a dual-RF system, simulations reveal that the peak current can be further reduced. This paper presents the simulation results and explains the underlying mechanism.