Investigation for FEL spectrum narrowing

将大电流电子束注入具有分布式反馈系统的摆动器中。观察到FEL振荡。得到了感应发射变窄的结果。结果如下：1)我们在1mm波长获得了600kW的超优势，频谱宽度<正负>20%，本cas2)使用分布式反馈，频谱宽度<正负>5%，实验结果用理论解释了3)我们获得的增益为30db/1.8m。我们正在总结结果，准备发表。正在规划高梯度加速等应用实验。

High current electron beam was injected into a wiggler with distributed feed back system. FEL oscillation was observed. Narrowing of induced emission was obtained. The results are as follows.1) We obtained a superadiance of 600kW in 1mm wavelength the spectrum width was <plus-minus>20% in this cas2) Using the distributed feed back, the spectrum width was <plus-minus>5% and the results of experiment, were explained by the theor3) The gain we obtained was 30db/1.8m.We are summarizing the results to publish. Application experiments are planning such as high gradient acceleration.