“School of Physics”

Back to Papers Home
Back to Papers of School of Physics

Paper   IPM / P / 6770
School of Physics
  Title:   Raman Free-Electron Laser with A Coaxial Wiggler
1.  B. Farrokhi
2.  B. Maraghechi
3.  J.E. Willett
  Status:   Published
  Journal: Phys. Plasmas
  No.:  55
  Vol.:  7
  Year:  2000
  Pages:   4266-4272
  Supported by:  IPM
A one-dimensional theory of the stimulated Raman scattering mechanism for a coaxial free-electron laser (FEL) is developed. The beam-frame FEL dispersion relation and a formula for the lab-frame spatial growth rate are derived. A numerical study of the growth rate for the coaxial wiggler is made and compared with that for the helical wiggler. Except for a part of the group II orbits, the growth rate is found to be less than the helical wiggler. Relativistic effects due to the transverse oscillation of electrons in the wiggler field prevent the FEL operation from approaching magnetoresonance. In the absence of these relativistic mass effects, the calculations show a magnetoresonance associated with the first spatial harmonic and a much narrower resonance at the third spatial harmonic.

Download TeX format
back to top
scroll left or right