D-He/sup 3/ fuel cycle for space propulsion system

Summary form only given, as follows. Summary form only given. An open-ended magnetic confinement fusion system which appears to lend itself nicely to a space propulsion system that can meet the stringent requirements of space exploration is examined. It is based on mirror magnetic configuration which has been studied for decades in connection with applications to the terrestrial power reactors, and whose confinement physics is reasonably well understood. What distinguishes this propulsion device from the conventional mirror reactor is the fact that the plasma in it is sufficiently dense as to make the collision mean free path much smaller than the dimension of the system thereby allowing the plasma to behave much like a fluid. Although D-T fuel cycle is desirable in early stages of development because of its low ignition temperature and less stringent technological requirements, D-He/sup 3/ is most often mentioned due to the fact that its reaction products are charged particles and its neutron production is minimal. When applied to the propulsion system considered in this work it is seen that a D-He/sup 3/ fuel requires a very high injection energy (>200 keV) to produce a reactor gain factor Q greater than unity.