In inertial confinement fusion (ICF) experiments, the high electromagnetic fields propagating through a relatively dense plasma can result in a transverse instability, causing the matter and light to form filaments oriented parallel to the light beam. We examine whether a similar instability exists in the electron beam of a free-electron laser, where such an instability could interfere with the transfer of beam kinetic energy into optical wave energy. We heuristically examine the instability in a relativistic beam through which an intense laser beam is propagating. We ignore the FEL effects. We estimate how the altered index of refraction in an FEL affects the dispersion relation. Finally, we estimate the effect that the instability could have on the phase coherence of a particle as it transits an FEL. 10 refs., 2 tabs.

The report consists of viewgraphs. (WRF)

This paper consists of viewgraphs on swept divertors and internal magnet coils for a Compact Ignition Tokamak design. The author concludes that poloidal field energy and volt-second considerations suggest a swept divertor scenario where the outboard strike point moves from small R to large R, while the inboard strike point moves from small Z to large Z. (LSP)