40
FREILING, CROCKER, AND ADAMS
ACKNOWLEDGMENTS
We are most grateful to Col. Irving J. Russell of the Air Force
Weapons Laboratories and Dr. John Norman of General Atomic DiviSion, General Dynamics Corporation, for permission to present their
data prior to publication.
APPENDIX
TERMS AND DEFINITIONS
RADIONUCLIDE FRACTIONATION Any alteration of radionuclide composition occurring between the time of detonation and the time of
radiochemical analysis which causes the debris sample to be nonrepresentative of the detonation products taken as a whole.
FRACTIONATED Two substances, either radionuclides or inert ma-
terial, are fractionated with respect to each other in a sample of
debris if they are not present in their representative ratio. The
term is meaningless when applied to a single substance.
*POTENTIAL FRACTIONATION
The existence of different composi-
tions in various portions of a sample of debris when these portions
are subject to separation by subsequent natural processes, é.g.,
the existence of particles of different size with different compositions in the same portion of a nuclear cloud or of a slurry in which
different nuclides are distributed between liquid and solid phases
in different proportions.
*NATURAL FRACTIONATION Fractionation produced by the processes occurring subsequent to detonation.
*PRIMARY FRACTIONATION IN AIR, TOWER, AND SURFACE BURSTS
Actual fractionation produced by meteorological, gravitational, and
centrifugal separation of potentially fractionated particles in a
cloud.
*SECONDARY FRACTIONATION IN AIR, TOWER, AND SURFACE
BURSTS Fractionation produced by interaction of the debris with
radioactively inert environment (e.g., leaching with water or pref-
erential small particle adsorption on surfaces).
*ARTIFACTITIOUS
FRACTIONATION
Fractionation resulting from
human intervention (e.g., biased sampling, incomplete decontami-
nation of collector surfaces, and faulty analytical techniques).
FRACTION OF CONSITITUENT OR EXTENSIVE PROPERTY IN A
SAMPLE
The ratio of the quantity of said constituent or property
to the total amount produced by the device and measured at the
same time whennecessary (replaces the “bomb-fraction” concept).
* Asterisks indicate convenient, but not essential, terms.