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Recollections re Bikinimeyr',- 0!
its ee
NOR tu
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Car RNS
Doe
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Zmierstion: You raised various aquesticna re Bivini.
These rre answered below,
with the information I have in my head. Better answers could be obtained
from Admiral Persons,
on from Dr.
H. P.
Scoville, Rm.
2A314, Pentegon
(re radioactivity), Comdr. Vaux of Office of “aval Reaearch (re remote
detection as by eprth shock), or Comdr. Roger Revelle (Navy ext. 2060)
re analysis of mud.
1. Bikin* Lafoon was entirely deserted for meny months in the sutumn of
1946 en* the first few months of 1947.
It wae in charre of officials
located at Kwajelein, about CO miles away.
2. Seismic methods were unable to detect Test Able at any annreciable
distance.
3. ty determining radioactive materials in the air, it was found possible,
according to some vnhysicists,
to detect Pest Able in western USA; but
according to other ochysicists, the signal to noise ratio was not
sufficient to accomplish such detectione~ using the imperfect
equivment and procedures then -vailable.
4. Seismic methods were able to detect Test Baker. My recollection is that
sensitivity wes sufficient for making the detection at several thousand
miles. But it is my recollection also that fetection in this instance
does not necessarily mean distinguishing an atomic bomb exnlosion from
netural seismic effects.
5. A fair fraction of the radioactive materials in Test Baker were thrown
into the air, and drifted to leeward. It is my recollection that the
velue of this fraction was Cetermined with very unsatisfactory accuracy;
also that detection of the exrlogion by measuring amount of radioactive
Materials in air was found not to be feasible at distance of, sry, a
fer thousand miles.
6. Some analyses were made,s'ortly after each explosion, tr show the
efficiency of the bomb; t»ese analyses were canable of revealing the
identity of the fissionable material used.
It is my impression also
that, in the year-later expedition to Ritini, further analyses were
mode, canable of s owing the efficiency dnd the identify of the
ficsionable material.
I do not know whether any analyses of this
time were made on radioactive materials found svnecifically in the
mad,
ee &
In the three-day conference starting Feb.
3,
1947,
on the results
of Operation Crossroads, it was brought out very clearly thet the remote
detection vroblem is a complicated one. Digtinguishing signels from noise
is a major question. Also, some methods might show sugrestion that an
atomic bomb exnlosioy hae occurred, but not vroof; other methods might
be good for proof once the suggestion had been advanced.
Some ~ethods
might s*ow the existence, but not the location, of an atomic exnlosim.
A full answer involves many kinds of information.
The whole matter is
beyond the extent of my !mowledge.
One woulé do well to confer with
the nereons mentioned above, or with Dr.E. Ss. Gilfillen, Technical Mrector
of the Joint Cros-roa‘s Committee.
DE
EG tasar
_
pack
I
REPOSITORY NARA Cotley
COLLECTION RG
326
her Files
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FOLDER
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TLS ts
STRATIVE MARKING
5, Section 6-10
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