Thermonuclear reactor

In a thermonuclear reactor, a neutron particle injection device at an energy of greater than 1 MeV is disposed and an element having a high reactivity with the element of beams is used for the material of the first wall. Neutron particle beams are ionized in plasmas into fast ions, and they are decelerated while colliding against electrons and ions of plasmas and finally thermalized, during which ions tens to cause nuclear reaction with impurities in the plasmas since the ions are fast. Impurities which caused nuclear reaction are converted to charged particles such as fast He, then thermalized in the plasmas and the plasmas are heated. If they are high temperature plasmas, the deceleration time is extended and the number of beam ions contributing to the nuclear reaction is increased, which is advantageous than in a case of using low temperature plasmas. Dilution of fuels due to impurities and lowering of plasma temperature caused by radiation loss can be prevented, to provide an effect of facilitating a steady operation of the thermonuclear reactor. Further, disruption is hardly caused and the plasmas are easily controlled. (N.H.)