Electron trajectory and growth rate in a two-stream electromagnetically pumped free electron laser and axial guide field

Mehdian, H.; Saviz, S.
September 2008
Physics of Plasmas;Sep2008, Vol. 15 Issue 9, p093103
Academic Journal
The effects of two-stream on electromagnetic wiggler free electron lasers (TSEMWFEL) with an axial guiding magnetic field are studied. An analysis of the two-stream steady-state electron trajectories is given by solving the equation of motion in the axial guiding magnetic field and the electromagnetic wiggler. Numerical calculations are made to illustrate the effects of the dual electron beam on the trajectories. The dispersion relation is derived employing linear fluid theory. The characteristics of the dispersion relation are analyzed numerically. The result shows that the growth rate is considerably enhanced in comparison with single-stream. The maximum growth rate is studied numerically as a function of axial guiding magnetic field for multiple electron trajectories. It is shown that the maximum growth rate of TSEMWFEL increases and decreases with respect to the axial guiding field for different trajectories.


Related Articles

  • Electrons trajectories in electromagnetically pumped free electron laser with a constant reverse guide magnetic field. OMAR, Ahmad // Turkish Journal of Physics;2011, Vol. 35 Issue 2, p145 

    An exact solution to the quartic equation in the wiggler frequency ωw, which represents the dispersion relation for this system, is obtained. The effects of the frequency of the wiggler ωw on the electron's velocities (vǁ and vw) are investigated. The regions of interest for the...

  • Explicit expression for growth rates in free-electron lasers with helical and axial magnetic fields. Demokan, O.; Kabak, Y. // Physics of Fluids B: Plasma Physics;Oct92, Vol. 4 Issue 10, p3382 

    The dispersion relations of transverse and longitudinal modes in a free-electron laser with helical and axial magnetic fields are derived exactly for the one-dimensional case. The modes with positive and negative helicity are distinguished clearly. An analytically solvable expression for the...

  • The influence of the guiding magnetic field on the performance of a Smith–Purcell amplifier operating in the strong Compton regime. Schächter, Levi // Journal of Applied Physics;4/15/1990, Vol. 67 Issue 8, p3582 

    Presents a study which investigated the influence of the guiding magnetic field on the performance of a Smith-Purcell free-electron laser operating in the strong Compton regime. Discussion of electron dynamics; Information on the response function of the Smith-Purcell amplifier; Results.

  • The linear theory of the circular free-electron laser. Saito, H.; Wurtele, J. S. // Physics of Fluids (00319171);Jul87, Vol. 30 Issue 7, p2209 

    A small signal theory of a free-electron laser (FEL) with a rotating electron beam in a uniform axial magnetic field and in an azimuthal wiggler field (the ‘‘circular’’ FEL) is developed. The analysis includes the low and high gain regimes and the influence of...

  • Electron beam transport in gas-loaded free-electron lasers. Yariv, Shalom; Friedland, Lazar // Physics of Fluids B: Plasma Physics;Dec90, Vol. 2 Issue 12, p3114 

    The effects of the presence of helical wiggler and axial guide magnetic fields on the quality of the electron beam in a gas-loaded free-electron laser are investigated. The electron velocity space diffusion theory in the free-electron laser is developed and tested in Monte Carlo simulations. The...

  • The controlling parameter of a wiggler-pumped free-electron laser with an axial-guide magnetic... San-kui Gou // Physics of Plasmas;Feb95, Vol. 2 Issue 2, p533 

    Focuses on basic equations of a wiggler-pumped free-electron laser with an axial-guide magnetic field. Evolution of the configuration; Critical value of the controlling parameter which contains the effects of the wiggler, the electron beam, and the guide field; Evolution property of the...

  • Generation of electromagnetic radiation from a rotating electron ring in a rippled magnetic field. Yin, Y. Z.; Bekefi, G. // Physics of Fluids (00319171);Apr85, Vol. 28 Issue 4, p1186 

    Calculations show that modes resembling the free-electron laser (FEL) instability are excited when electrons move in quasicircular orbits under the combined action of a uniform axial magnetic field and an azimuthally periodic wiggler magnetic field. In.the model, a thin annular ring of rotating...

  • New class of unstable orbits of the equilibrium electrons in free-electron lasers. Zhang, Shi-Chang; Zhang, Zhong // Applied Physics Letters;10/2/1989, Vol. 55 Issue 14, p1380 

    We present a theoretical prediction of a new class of unstable orbits of the equilibrium electrons in free-electron lasers, which is entirely associated with the radial self-electric field and azimuthal self-magnetic field. It is also pointed out that these self-fields may deteriorate the beam...

  • Kinetic description of harmonic instabilities in a planar wiggler free-electron laser. Davidson, Ronald C. // Physics of Fluids (00319171);Jan86, Vol. 29 Issue 1, p267 

    The linearized Vlasov-Maxwell equations are used to investigate harmonic stability properties for a planar wiggler free-electron laser (FEL). The analysis is carried out in the Compton regime for a tenuous electron beam propagating in the z direction through the constant-amplitude planar wiggler...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics