Study of long range beam-beam effects

The operation of colliders are often limited by the nonlinear effects of be am-beam interaction, especially for the strong current machines, such as BE PCII (BEPC multibunch collision scheme). The beam-beau interaction in BEPCI I is very complicated. The bunch will collide with another bunch head on at the south interaction point and interact with another bunches due to the l ong distance beam-tram force at other eleven points along the ring. This pa per has studied the tune shift and tune spread due to the long distance bea m-beam interaction effects. The long distance beam-beam effects of BEPCII i njection mode have also been studied.