HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Ross, D. A. Articles by Harris, C. C. Search for Related Content PubMed PubMed Citation Articles by Ross, D. A. Articles by Harris, C. C.

Quantitative Counting in the Presence of Coincidence-Summing Scintillations¹

Oak Ridge, Tennessee

ABSTRACT

Certain radionuclides emit pairs of photons so nearly simultaneously that if both members of the pair reach a detecting crystal the effects of their scintillations are additive. This makes the pulse-height spectrum depend on the detector geometry, and the only safe way to avoid trouble, in quantitative counting, is to count the unknown sample and its standard of comparison in the same geometry. When accurate duplication of the geometry is not possible—for example, if the unknown is inside a patient—the errors can be reduced by proper selection of the energy band. When high-geometry assay procedures are used, the coincidence-summing probabilities must be carefully taken into account.

FOOTNOTES

¹ Research sponsored by the U. S. Atomic Energy Commission under contract with the Union Carbide Corporation.