cr feen ee aee Nt ee . at nt Aee A ne ee a me ntl ABSTRAC The-objective of-Projeet—-2.2-was-to ceasure jnitial- and residual-gacca ratas,as a functlon of time at various distances from high-yield thermo- nuclear detonations, Initial-ganua rate versus tice was beacured at fiod distances from ground zero. In particular, measurcoants wore sade of the offact on initieal-gacsa rate caused by the passsge of tha shock front fron ground zero through the detector station. $ Rasidual-ganma rate versus tine was measured to provide gamza> wee wetfctlon is of nighicitle elenifepba in tha eedittenca Iosa mM ad Pe posaltts only Lf perucenal sronispyroot tuners, me ns ye a Te «z eric It erprsra that the 4 deanse, teeenzy clash esd th £0 great by conrarisen tha wats disposed inside blaust- and CF be 9) (sea Fleuy 4.1). we wha rate of arrival end geasa-fisld-decay rate during the 36-hour period after tha detonatica. Scintillation detectors wre used in making mecsuurenints. The in strumant atations were self-containud--~the only outsida facilities required wes timing slgnaia ta turn on the stations at a predetermined tine prior to thea detonation. Data ovtuined indicats that the expanding fireball and the passage of tha shock front from ground seve through the detector station hada marked affect on tha initial-gerra ratecs-isnea cn the integra sd oor gure. The initdal~gaziza rate reacted its first peak imisiiately after tre datoration, decreased slowly, begen to rise slowly, sei thon Incressed repidly to a second peak (which was about the sate value as the first peak). After reaching the second-peak valua, the Initial-gana rate dae exeasad rapidly to sero. The slow decrease jAInitial-gama rats was attributed to the nmatuc ral decay of the rission products; the slow rica, to tha axoseding of tha dreball and epproach of ths shoex front; and thea renid incroase, to tha pasce.a ef the shock front Yhrough tha dutector etation. Those effects war) olso evidenced in tha intogrs ted exeosure both prior amd subsiqusat to ths arrival of the ehock front. Ths avverea welosity of tha shoe froat waa found to desrvans rapidly vith gistenes Erea grovrd esro. Tha decay exconent froa tha raviducl centuntastion and flout vase Jed with distonsa ced direction fron prourt coro, ard its choclate yaiue insreasad rather abrocbly cevoral houra efter tha @atenation. This abrupt increase ig agtributele ta the procenee of chort~livad trotopes in tha resdtuel contentination and frJlout. Tha roasurecints ecda by Pooject 2.2 of initlale. 7a redi-tion ex posuras from thiivonuclear coyicsa of nish ylold em in coeds wectens with data from "The Ruclear Readahion foriwok,t ATP LD 9 ee een ere meets te rediation tims-intensity data, which give information beth on fallout pene ee we AeRE nee ROECm - ere pen a ner cowry co ee ee aww ce