BIAS IN FALLOUT DATA FROM NUCLEAR SURFACE SHOT SMALL BOY AN EVALUATION OF SAMPLE PERTURBATION BY SIEVE SIZING
Abstract
Evaluation of sample bias introduced by the mechanical sieving of Small Boy fallout samples for 10 minutes revealed the following: Up to 20% of the mass and 30% of the gamma-ray activity can be lost from the large-particle (greater than 1400 microns) fraction. The pan fraction (less than 44 microns) can gain in weight by as much as 79%, and in activity by as much as 44%. The gamma-ray spectra of the fractions were not noticeably altered by the process. Examination of unbiased pan fractions (before mechanical sieving) indicated bimodality of the mass-size distribution in a sample collected 9,200 feet from ground zero, but not in a sample collected at 13,300 feet.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 26, 1967
- Accession Number
- AD0820147
Entities
People
- Juan N. Pascual
Organizations
- Naval Radiological Defense Laboratory