and eventually become the najer contributor. This applies enly to Gevices with yields ef lees than 100 kt, in whieh the Ayfrodynanis effect is small. Figure 1.1 show the contribution from fission-produst games ent #* (n,)) for a l-kt surface burst. With respect to time, the #* (na,) radiation is essentially exitted within 0.2 second; the fissicaproduct games, however, continue to contribute for the first 30 secenis. Por Ghermonuciear devises, in afdition to gamma rediiaticn fren fiesion-product gammas, it is necessary to consider the interaction of neutrons from the fusion process vith ¥'*. me radiation due te the fusion process may vary over wide limita depending on the design ef the Gevice. For a given yield, the sumber of neutrons available aay be ten times as great for fusion es for fission, and thereforea largemumber"Or Game photons are contributed ty the H°* (n,/) reactions (Reference 9). Hovever, veceuse of the ghert half-life, this gaama radiation decays defore it can be enhaneed by the Bydrodynenic effect. Gemmas fren the Longer-lived fission profmets are greatly eohanced dy this effect. Therefore, fission prodects are the most inportant source of initial guum exposure resulting from high-yield fission-fusion devices. 2.3.2 Residual Gemma Radiation. sY. gies oa ‘The restiualgame rediation eonsista of fisdion-product refiation from falleut end radiation fren neutroo-inéuced activity. ‘fhe decay rate of the residual rediation fron fallout will follow approximately the expressions: ~]1.2 2 yt and re [Px at 2 52,(t,6.2to? ) where: . (2.2) yy FENERGY ACT OF 13% /7