JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - UNPB AU - Zhang, Y. AU - Migliorati, M. AU - Ohmi, K. AU - Wang, N. AU - Zhou, D. AU - Zobov, M. ED - Biagini, Maria Enrica ED - Chrin, Jan ED - Giabbai, Manuela ED - Iungo, Massimiliano ED - Schaa, Volker R.W. TI - Beam-beam Simulations including Coupling Impedance J2 - Proc. of eeFACT2022, Frascati, Italy, 12-16 September 2022 CY - Frascati, Italy T2 - ICFA Advanced Beam Dynamics Workshop on High Luminosity Circular e+e- Colliders T3 - 65 LA - english AB - The design performance of future e⁺e⁻ ring colliders has been pushed to new extreme based on the crab-waist scheme. The new found coherent head-tail instability (X-Z instability) may induce the horizontal beam size blowup and reduce the machine performance. The longitudinal coupling impedance would distort the phase space: lengthen the bunch and bring incoherent synchrotron tune spread. The simulation study has found the clear influence of longitudinal impedance on the X-Z instability in both CEPC and FCCee. With the evolvement of future machine design process, the transverse impedance has also been included. The results show that a vertical beam-beam TMCI-like instability may be induced when the impedance is considered. It is first found in e⁺e⁻ colliders. Some similar study at SuperKEKB will also be presented. It could be expected or concluded that different effect would couple and determine the final performance together in present and future high performance crab-waist colliders. Separate effect study seems not enough to evaluate and predict the machine performance/stability. PB - JACoW Publishing CP - Geneva, Switzerland ER -