TOROIDAL ELECTRON-BEAM RADIATION SOURCES

Permanent magnet structures based on magic spheres and magic toroids a fford the possibility of synchrotron and wiggler radiation sources in which the electrons describe circular mean paths rather than the usual rectilinear ones. We analyze toroidal structures with uniform fields in their interior cavities which cause injected electrons to follow ci rcular paths thereby emitting synchrotron radiation. If azimuthally pe riodic iron '' teeth '' are spaced about the principal circumference, the resulting periodic field causes the electrons to oscillate radiall y at right angles to their orbit, giving rise to wiggler radiation. Co mputer calculations for sample structures show that for a toroid of pr incipal radius 12 cm, outer sectional radius of 4 cm and inner section al radius 1 cm, beam slot width of 3 mm and azimuthal period of pi/4, the resulting mean field is 2.35 T, the peak to Peak field amplitude 1 .1 T, the electron beam energy 8.6 x 10(7) eV and the angular frequenc y of emitted radiation 9.4 x 10(16) Hz. Synchrotron radiation of one-e ighth the frequency of the wiggler frequency is always emitted and sup erimposed on the wiggler radiation in the periodic structure.