Fission Product Radioactivity in the North Polar Stratosphere.
Balloon-borne gamma-ray detection equipment flown from Thule, Greenland, during April 1962, indicated that there was considerable radioactivity above 70,000 feet. Gamma-ray spectra obtained indicated the source of much of the activity to be the Soviet nuclear tests in late 1961.
Gustafson
P F
PF
Keener
R B
RB
McGinnis
G A
GA
Soller
R A
RA