（2+1）维Sawada-Kotera方程中两个Y周期孤子的相互作用

利用双线性方法给出了2+1维Sawaka-Kotera(SK)方程的N孤子解.将N孤子解中的实参数扩大到复数范围，得到了该方程的呼吸子解，描述线孤子和y周期孤子相互作用的解和两个y周期孤子相互作用的解.从解析和几何两个角度探讨了两个y周期孤子的相互作用.相互作用性质和耦合系数有关.对于SK方程，耦合系数的取值只允许方程中存在弹性的排斥相互作用. 关键词： y周期孤子相互作用 SK方程 双线性方法

Interactions between two Y-periodic solitons in the (2+1)-dimensional Sawada-Kotera equations

The exact solutions of the (2 1) dimensional Sawada Kodera(SK) equation are presented by using the bilinear method.The N breather solutions,the solution to describe the interaction between a line solition and a y periodic soliton and the solution to express the interaction between two y periodic soliton are included in the exact solutions.Detailed behaviors of interactions between two y periodic solitons are illustrated both analytically and graphically.For SK equation,the value of interactive constant can only be taken in some range.We can only obtain the repulsive interaction that keeps the shapes of soliton unchanged.