Toroidal electron beam radiation sources

Permanent magnet structures based on magic spheres and magic toroids afford 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 circular paths thereby emitting synchrotron radiation. If azimuthally periodic iron “teeth” are spaced about the principal circumference, the resulting periodic field causes the electrons to oscillate radially at right angles to their orbit, giving rise to wiggler radiation. Computer calculations for sample structures show that for a toroid of principal radius 12 cm, outer sectional radius of 4 cm and inner sectional radius 1 cm, beam slot width of 3 mm and azimuthal period of π/4, the resulting mean field is 2.35 T, the peak to peak field amplitude 1.1 T, the electron beam energy 8.6×10⁷ eV and the angular frequency of emitted radiation 9.4×10¹⁶ Hz. Synchrotron radiation of one-eighth the frequency of the wiggler frequency is always emitted and superimposed on the wiggler radiation in the periodic structure