Abstract: A rapidly pulsed nuclear fusion reaction system including a firing chamber into which synchronized opposing beams of ionized gas such as deuterium/tritium are injected in the form of ion pulses which are adapted to collide at the mid point of the chamber. The pulsed ion beams are fed through respective orifices across which is applied a relatively high DC voltage. External to the firing chamber is means for generating a pulsed magnetic field interiorally of the chamber along the ion travel path and in synchronism therewith to provide a guiding effect of the two opposing ion beams to the precise center of the firing chamber. At the moment the leading edges of the ion beams meet, an electric arc is developed due to the voltage applied across the orifice.