The electron back bombardment phenomenon, which results in anomalous increase of gun current emission, has been observed in a series of our side coupled standing wave accelerating tubes.
The cathode of the gun may be partially shielded magnetically. The paraxial-ray equation for describing the electron trajectory in the accelerating region is solved in closed form.
阴极处磁场可以具有任意屏蔽程度，得到了在加速场内描写电子轨迹的傍轴方程的解析解。
3
The thesis mainly discusses accelerating process of the first flyer and the optimization design of the second flyer for two-staged electric gun.