uc, ALAMOS SCIENTIFIC LABORATORY § | UNIVERSITY IDF CALIFORNIA LOS ALAMOB, NEW MEXICO OFFICE MEMORANDUM TO Gaelen Feit, J=15 DATE: FROM Tom White, H6 SUBJECT: SOMS NOTES ON AN OPTICAL FALLOUT AKALOGUE SYMBOL : Hb June 2h, 1955 o 407608 BEST COPY AVAILABLE This refers to some points in your 17 June memo on the above Bubject, AS noted in our conversation this morning, the discrepancy b@tween differertiéls was overlooked in auoting our fallrate functiog to yous Your equation on page 9 should be | : F(Af)at= _o2 S (4) Jar exp -+ 2 fmt -ine, () 2 O74) - \oa (ime) so that some of your subsequent numerical calculations shoul be reduced by With regard to the values of f and Sused during rost of following should be noted, (ie took the Weather Bureau com fitted the activity vs particle size data for each cloud la normal distribution, The fit turned ovt to be surprisingly reessonable error, the mean log particle diameter wes a line mAPOT, the site model, and er to a log afactor f, height, end the standard deviation was independent of heizh good, Within r function of in an effort to make our rachine calculetion reproduce thes features of the eather Bureau model, we then used the aerodynamic theory f r spherical uvuld put appro: particles to convert. to effective values of f,, and Othat imately the same distribution on the ground from a &0,000 oot cloud, If one assumes that in a higher cloud, the sane activity v Giameter would wiesther Bureeu data, this is the only rezsenable assumptiowg that we can exist at the same fractional heisht, then the effective f would come cut differently. It seems to me that if we went} make, we may then want to have two sets of and one for MT clouds, f and g~ values to use the end G~ vafues; one for kT I hope soon to have some calculatidns that will tell how much difference it rixsht mike. Tw: bg yeu Distribution: Si chleer, H-46 Be "Ali Re watt, J=-16 RG Thom 326 US ATOLL EXER! COUNTS108 H, Eoerlin, J-10 Lorat o__EAR | L, Cérdner, GA A, Eord, J-7 1 sileection e Gl pelt? 3-15 Bralec We Czl Te whitey TOG E-5 Felder e white x 1 Eto lect n\

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