Plasma cyclotron radiation and fusion reactors

The theory of cyclotron radiation from high-temperature plasma confined within a magnetic field is applied to the estimation of the radiation loss from plasma confined in fusion reactors. It is shown how a metallic reflector placed around the plasma should limit the seriousness of this loss. In the case of a mirror machine, comparison is made with the mirror loss and the electrical power dissipated in the coils producing the magnetic field. Ratios of power lost are found as functions of β/η (plasma to magnetic pressure ratio/absorption coefficient of the reflector) and β BR ( B is the field strength, R the mean radius) which are also compared with the nuclear yield. For the stabilized pinch and stellarator, cyclotron loss is compared with nuclear yield. With β not less than 0.1 it is shown that cyclotron loss can be unimportant in all three types of D-T reactor. For the D-D mirror machine the minimum necessary value of BR would be about 2 × 10 8 gauss cm, whilst for the pinch or stellarator the minimum necessary current or BR , based only on radiation loss, is 18 × 10 6 amperes or 3.5 × 10 6 gauss cm respectively.