中国物理B ›› 2014, Vol. 23 ›› Issue (2): 24102-024102.doi: 10.1088/1674-1056/23/2/024102
• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇 下一篇
Saviz Sa, Lashani Ea, Ashkarran Ab
Saviz Sa, Lashani Ea, Ashkarran Ab
摘要: The theory for the two-stream free electron laser (FEL) consisting of a relativistic electron beam transporting along the axis of a helical wiggler in the presence of an axial guiding magnetic field is proposed and investigated. In the analysis, the effects of self-fields are taken into account. The electron trajectories and the small signal gain are derived. The characteristics of the linear-gain and the normalized maximum gain are studied numerically. The results show that there are seven stable groups of orbits in the presence of self-fields instead of two groups reported in the absence of the self-fields. It is also shown that the normalized gains of three groups decrease while the rest increase with the increasing of normalized cyclotron frequency Ω0. Furthermore, it is found that the two-stream instability and the self-field lead to a decrease in the maximum gain except for group 3. The results show that the normalized maximum gain is enhanced in comparison with that of the single stream.
中图分类号: (Free-electron lasers)