Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-25T06:44:49.819Z Has data issue: false hasContentIssue false
  • English
  • Français

Optimization of Liquid Scintillation Counting for 14C Dating∗

Published online by Cambridge University Press:  18 July 2016

Fernando E Angiolini  and
Miguel C Albero
Fernando E Angiolini
Affiliation:
INGEIS, Instituto de Geocronología y Geología Isotópica, Ciudad Universitaria–1428 Buenos Aires, Argentina
Miguel C Albero
Affiliation:
INGEIS, Instituto de Geocronología y Geología Isotópica, Ciudad Universitaria–1428 Buenos Aires, Argentina
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The effects of different measurement conditions and sample preparation in liquid scintillation counting of benzene for 14C dating were tested. The goal of this work was to find the highest figure of merit through the variation of scintillation cocktail to benzene ratio, and measurement windows. Measurements were performed on 5ml of benzene plus increasing quantities of scintillation cocktail (7g of PPO and 0.5g of Me2POPOP in 1L of scintillation-grade toluene). Spectra of both background and standard were obtained and the counting windows selected for the highest figure of merit (Q). The best condition was 5ml of benzene plus 0.75ml of scintillation cocktail. This spectrum is compared with that of 1) pure toluene-14C plus cocktail, and 2) pure benzene-14C in which the equivalent amount of PPO and Me2POPOP present in 0.75ml of cocktail was dissolved. A correlation between the increase of the amount of cocktail and the broadening of the spectrum was observed. The effect of wrapping the upper part of the counting vial with aluminum foil to reduce background was also tested. A drastic background increment was observed in the low energy range, for unwrapped vials; the standard spectrum showed a broadening and a lower counting efficiency which reduced the figure of merit.

Type
V. Conventional Techniques
Information
Radiocarbon , Volume 28 , Issue 2A , 1986 , pp. 597 - 602
Copyright
Copyright © The American Journal of Science 

References

Birks, J B, 1977, Impurity quenching of organic liquid scintillators, in Crook, M A and Johnson, P, eds, Symposium on liquid scintillation counting, Proc: Heyden & Son Ltd. Google Scholar
Florkowski, T, Grabczak, J, Kuc, T and Rozanski, K, 1977, Determination of radiocarbon in water by gas or liquid scintillation counting, in Povinec, P and Usacev, S, eds, Internatl conf on low radioactivity measurements and applications, Proc: Bratislava Slovenske Pedagogick Nakladatelstvo.Google Scholar
Parker, C A, 1968, Kinetics of photoluminiscence (Chapter 2) and apparatus and experimental methods (Table 25), in Photoluminiscence of solutions: Amsterdam, Elsevier, 544 p.Google Scholar
Wehry, E L, 1967, Structural and environmental factors in fluorescence, in Guilbault, G G, ed, Fluorescence: theory, instrumentation and practice: New York, Marcel Dekker Inc 697 p.Google Scholar