The coupling envelope equations for bunched beam in a linac have been derived by means of the forces induced by a cylinder model of space charge of the bunched beam in waveguide.

• 采用直线加速器中有限圆柱空间电荷模型，利用电荷束团所产生的纵向和横向空间电荷力，推导得到了直线加速器中计入纵向与横向耦合效应的电荷束团的耦合包络线方程；