Effects of initial radiation with focus on neutrons

Results from calculations using KlangVerk are presented and damage radii for different detonation heights and weapon effects are illustrated. Heat radiation gives the largest damage radius for loss of combat effectiveness outdoors. Inside a tank, the initial radiation has the largest damage radius if the yield is less than ~100 kt. If the yield is larger, the blast wave gives the largest damage radius. In addition, results are presented for enhanced radiation weapons. Damage radii presented in a FOA-paper from 1977 were recreated. It appears that the assumption was made that 35% of the energy was released as blast wave and heat radiation. To reach this low percentage one has to assume that all of the fusion neutrons leave the weapon residues as initial radiation, which is not the case. Despite the underestimation of effects of blast wave and heat radiation, the difference in damage radius for an enhanced radiation weapon and a regular nuclear weapon is moderate. Simulations using MCNP show that both humid air and detonation above water gives smaller damage radius for initial radiation. A reasonable shielding factor for a tank is 0.25 and neutron activation of the tank does not imply any direct limitation of the combat effectiveness.