光学渡越辐射理论及其在直线感应加速器脉冲电子束诊断中的应用

匀速运动的带电粒子在穿过具有不同介电常数的两种媒质界面时要产生所谓光学渡越辐射。该辐射在粒子的入射平面上呈偏振行为;从辐射强度的角分布可以确定入射粒子的能量。在入射到双膜系统的情况下,由于干涉的发生,在第二膜前表面的强度角分布有振荡行为。利用这些现象,可对脉冲电子束包络半径、束电流密度的横向分布,束能量以及横向散角进行测量,依照这一原理在各LIA加速器上进行的脉冲电子束参数测量,获得的有效数据极大地提高了加速器的调试效率。

Theory of optical-transition radiation and its application to pulsed electron beam diagnoses on linear induction electron accelerator

It is can be bring optical-transition radiation(OTR) when the charged partical constant speed passed through interface of two dissimilarity intermedium. The radiation showed polarization behavior while the charged partical arrive at incidence plane, it is can be confirm energy of incidence partical corresponding OTR angle distribution patterns. The OTR angle distribution had polarization behavior at secondarily foil’s surface due to interference happened while electron beam entered the double foil system. It is can be measure parameter of pulse electron beam by used these phenomenon, The parameter includes electron beam envelope radius, landscape orientation distribution of electron beam current density, and electron beam energy, electron beam landscape orientation divergence angle distribution. using this theory to measure parameter of pulse electron beam basing on a series of Dragon LIAs and obtains valid time-resolved results. This measurement ability has improved greatly the debugging efficiency of a series of Dragon LIAs.