Effects of the axial magnetic field component on the electron trajectory in the wiggler section

A section of a wiggler with SmCo/sub 5/ magnets was designed to be utilized in an infrared free-electron laser (IRFEL). The choice of low-cost small magnets resulted in a small gap in the wiggler (/spl les/10.0 mm). This gap size accentuated the edge effects, thus making the profile of the magnetic field more susceptible to distortion. The solution of the magnetic field component was obtained from finite-element computer codes and measurements of the magnetic field distribution in the inner region of the wiggler were performed. Effects of the axial magnetic field component on the electron beam trajectories were studied using a single-particle model neglecting collective effects.