RESULTS OF THREE-YEAR SYSTEMATIC MEASUREMENTS OF NUCLEAR FALLOUT

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Sb. Ved. Praci Lekar. Fak. Karlovy Univ. Hradci Kralove, Suppl.

OSTI ID:4053863

Santholzer, V

A survey is preserted of results of the measurement of radioactivity in rainout from November 1, 1956 to April 15, 1960, and in fallout from November 1, 1958 to April 5, 1960. The results demonstrate the temporary cessation of nuclear tests by November 1, 1958. Cumulative activity in the course of the second half-year after the stopping of nuclear tests decreased to 45% of cumulative activity of the first half-year (from November 1, 1958 to April 30, 1959). By the end of 1959 a further decrease appeared. Rainout activity levels reached three maxima (of increasing height) over the period studied, centering about August 1957, April 1959, and March 1960. Closer analysis of the last maximum shows a very large increase of activity on March 1, 1960 (corresponding to the first Sahara test) and a lower maximum on April 9, following the 2nd test. The fallout maximum corresponding to the first Sahara test occurred on March 2, l960 and reached approximates 18 mC/km/sup 2//day on that date. By March 31, it had fallen to 0.01 mC/km/sup 2// day. Regularities in the temporal decrease with time in the activity of fallout are shown. On the basis of longterm observations, it is shown that samples of fallout with large activity have relatively very small admixtures from the previous nuclear tests, so that in a period of several weeks or even months they can be considered as practically separke samples of fission products. The exponent n in the disintegration formula A = at/sup -n/ is most frequentiy equai to 1.2 for the period of the first 3 to 4 months after detonation. For older samples of fallout, n is equal to 1.5 in most cases. Energy of BETA and gamma rays from the fallout was estimated on the basis of absorption measuremerts. It was shown that the quality of BETA radiation varies with the age of the samples of fa1lout. (BBB)

• Research Organization: Charles Univ., Hradec Kralove, Czechoslovakia
• NSA Number: NSA-18-018049
• OSTI ID: 4053863
• Journal Information: Sb. Ved. Praci Lekar. Fak. Karlovy Univ. Hradci Kralove, Suppl., Journal Name: Sb. Ved. Praci Lekar. Fak. Karlovy Univ. Hradci Kralove, Suppl. Vol. Vol: 5
• Country of Publication: Country unknown/Code not available
• Language: Czech

Related Subjects

ABSORPTION
BETA PARTICLES
FALLOUT
FISSION PRODUCTS
GAMMA RADIATION
GEOLOGY AND MINERALOGY
LEVELS
MEASURED VALUES
NUCLEAR EXPLOSIONS
RAIN