CADMIUM-109 RESULTS FOR UP TO 20 KM
M. I. KALKSTEIN, A. THOMASIAN,
and J. V. NIKULA
Air Force Cambridge Research Laboratories, Bedford, Massachusetts
ABSTRACT
About 0.25 Mc of '°°Cd was produced as a unique tracer in the U. S.
Starfish
test
of July 9,
1962, detonated at 400 km above Johnston
Island, Subsequent measurements of samples
collected up to about
20 km revealed an increase in concentrations at high latitudes in the
southern hemisphere in the spring of 1963. This increase was coincident in time with the usual warmings in the southern-hemisphere
polar stratosphere. The increase in the northern hemisphere occurred
late in the winter of 1963-1964 and did not reach the values measured in the southern hemisphere. Meteorological observations indicate that this winter was quite mild in terms of disturbances in the
polar region, with the principal disturbances occurring late in the
winter. Stratospheric concentrations measured thus far correspond
to roughly one-half of what was expected on the basis of the }**Rh
experiment,
INTRODUCTION
About 0.25 Mc of '®Cd was produced as a unique tracer during
Operation Dominic I in the U. S. Starfish test of July 9, 1962, detonated
at 400 km above Johnston Island, Cadmium-109 (470-day half-life)
decays by electron capture to /°?™Ag (39 sec), which in turn decays by
an 88-kev isomeric transition to the ground state. In addition to the
109Cq, about 0.13 Mc of the long-lived isomer '!°™Cd, a 0.58-Mev beta
emitter, was calculated as having been produced.’
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