枝本 雅史

Laser fusion rocket can achieve large thrust and high specific impulse by utilizing huge amount of fusion energy to heat up a propellant. One of the issues of this system is heavy neutron shields which are heated by neutrons. The propulsion performance of a conical target that can reduce neutron radiation to the coil is calculated by numerical analysis. The impulse bits of the spherical and the conical targets are 12 Ns and 0.75 Ns, respectively, and the propellant in the conical target does not contribute to the thrust. This result suggests that the target shape should be optimized to establish both the neutron shielding and large thrust.