In an accelerator or a storage ring, Q magnets are used as focusing units.If their horizontal places deviate from the designed ones, beam orbit deformation will occur.

• 摘要Q铁（四极铁）在同步加速器或储存环中担任聚焦元件，如果它们的横向位置偏离了设计值，加速器将产生束流轨道的畸变。