9 SEED SEC ¢ — SESIDUAL RADIATION PATTERN FOR VARIOUS SURFACE WIND VELOCITIES - UNDERWATER ATOMIC BURST: i fssy | | tn | ASMES FORCES ee dad ties rheags ; | SPECIAL wEnPONS PROJECT APx G1 igsZ f Staff Study by Maj. T. A. Gibson, Jr., USA, 14 March 1952 In the event of an underwater atomic explosion in a harbor, it is. of interest to have estimates of the extent and magnitude of the | } is possible to make such estimates by using the information available from the Bikini-Baker underwater explosion. | ' ; ee residual radiation field as a function of surface wind velocity. ay | bet yt i aI q. ase mais KE — o! "4 toy sq i wits o It Figure 8.101 of "The Effects of Atomic Weapons" (2) will be assumed to be correct. (Assumption No. 1) This gives the dose rate at l hour after the explosion as observed on ships. Had the contamination fallen on land, the rates would be increased by about a factor of four due to the absence of run off and the presence of a greater contaminated area. That is, after a short time, a ship: is ot ' 1 & limited contaminated area surrounded by an essentially uncontaminated area. The final results of this paper should be multiplied by & to | be made applicable to land adjacent to an underwater burst. sd g a Sg! , ay Roger Revelle, in his "Characteristics of the Base Surge,” (2) gives the observed movement of the Bikini-Baker surge. He also gives predicted surge movement for other surface winds. These will be essumed to be correct. . { {Assumption No. 2) 3 4 4 g i ars —SSi The pattern of the Bikini residual contamination was observed go comes from the base surge. g wf deposition of contaminant can be expressed as: eS . al « . (Assumption No. 3) a = = Ke Integrating and letting, | . ty _, a . aD where: K is a constant to be determined = time of explosion t, = time surge reaches an area t, = time surge leaves an area t *9 Ki? - QS Saree : poy - Re “ a ~ -f Ns dt Core 7 CURITY INFORMATION . _— . RESTRICTED © ae eM t, = J er bos , The fourth and final assumption will be that the time rate of a3| afm ‘ to lie in an area almost identical with the area covered by the base surge. It. will be assumed that all of the residual contamination . tee , a ‘ J