LIBet

( continued)

which; 3 minutes I think it is.

Tnen finally 1t gets db

During the period of a ainute here, or four or five ninu

here, but particularly this minute here, the fireball
have cooled down to the point where aost of the phe
wnich decide the particle size distritution of the fallo
are over.

‘ow you have the picture which is rather fri

ening in soae respects, that this most dangerous fission

product is now leisurely deposited on the outside of all
of the dust particles {t touches in a nice aoluble avail
able fora so that it will desolve in water.

This would

one thing that distinguishes it from the other fission

products and aaxes the present data - [ ‘woulda't say wor

less — but one certainly must check to see whether there
isn't an enorsous fractionation of sp as coapared to

ordinary fission product.

Mr. Spence was telling me that

this was true in the case of Sr°?, which has a sistler
precursor history, though that krypton is a longer life

thing.
TELL=R:

Is the chain that you have put on the board quantitative,
in other words does all strontium cone from krypton?

LIBEYs

Cc.

he

Ag far as we know this is s0.

A.:AWS a

i'd like to say that we've analyz:d some of the UREANHO
fallout radiochezically and there was far less strontius

é7

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