Transverse resistive-wall instability of a bunched electron beam in a wiggler

The transverse motion of a beam traversing a narrow beam pipe is modified by resistive-wall effects. Depending on the strength of the focusing force from the alternating wiggler field, the effect ranges from a modification of the oscillation to a growth in transverse displacement with the length of pipe. This transverse effect saturates after a number of bunches have passed. The saturated transverse effect depends only on the pipe radius b (it increases as 1/b), but is independent of the thickness τ and conductivity σ of the pipe. However, τ and σ affect the time needed to attain saturation. 5 refs., 2 figs., 1 tab