中国物理B ›› 2013, Vol. 22 ›› Issue (7): 75205-075205.doi: 10.1088/1674-1056/22/7/075205

• PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES • 上一篇    下一篇

Dispersion relation and growth rate for a corrugated channel free-electron laser with a helical wiggler pump

A. Hasanbeigi, H. Mehdiank   

  1. Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614, Iran
  • 收稿日期:2012-10-09 修回日期:2013-03-04 出版日期:2013-06-01 发布日期:2013-06-01

Dispersion relation and growth rate for a corrugated channel free-electron laser with a helical wiggler pump

A. Hasanbeigi, H. Mehdiank   

  1. Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614, Iran
  • Received:2012-10-09 Revised:2013-03-04 Online:2013-06-01 Published:2013-06-01
  • Contact: A. Hasanbeigi E-mail:hbeigi@tmu.ac.ir

摘要: The effects of corrugated ion channels on electron trajectories and spatial growth rate for a free-electron laser with a one-dimensional helical wiggler have been investigated. Analysis of the steady-state electron trajectories is performed by solving equations of motion. Our results show that the presence of corrugated channel shifts the resonance frequency to smaller values of ion channel frequency. The sixth-order dispersion equation describing the coupling between the electrostatic beam mode and the electromagnetic mode has also been derived. The characteristic of dispersion relation is analyzed in detail by numerical solution. Results show that the growth rate of instability in the presence of corrugated ion channels can be greatly enhanced relative to the case of an uniform ion channel.

关键词: corrugated ion-channel free-electron laser, growth rate, helical wiggler

Abstract: The effects of corrugated ion channels on electron trajectories and spatial growth rate for a free-electron laser with a one-dimensional helical wiggler have been investigated. Analysis of the steady-state electron trajectories is performed by solving equations of motion. Our results show that the presence of corrugated channel shifts the resonance frequency to smaller values of ion channel frequency. The sixth-order dispersion equation describing the coupling between the electrostatic beam mode and the electromagnetic mode has also been derived. The characteristic of dispersion relation is analyzed in detail by numerical solution. Results show that the growth rate of instability in the presence of corrugated ion channels can be greatly enhanced relative to the case of an uniform ion channel.

Key words: corrugated ion-channel free-electron laser, growth rate, helical wiggler

中图分类号:  (Free-electron devices)

  • 52.59.Rz
41.60.Cr (Free-electron lasers) 52.27.Ny (Relativistic plasmas)