Hostname: page-component-7b7567c8c-2n9c9 Total loading time: 0 Render date: 2026-11-15T14:38:03.437Z Has data issue: false hasContentIssue false
  • English
  • Français

High-Performance 14C Gas-Proportional Counting System Applying Pulse-Shape Discrimination

Published online by Cambridge University Press:  18 July 2016

Osmo Äikää,
Pertti Mäntynen and
Tuovi Kankainen
Osmo Äikää
Affiliation:
Geological Survey of Finland, SF-02150 Espoo, Finland
Pertti Mäntynen
Affiliation:
Geological Survey of Finland, SF-02150 Espoo, Finland
Tuovi Kankainen
Affiliation:
Geological Survey of Finland, SF-02150 Espoo, Finland
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 new 14C dating system of the Geological Survey of Finland consists of three CO2 proportional counters of conventional size, a liquid scintillation anticoincidence guard, and a passive shield of about 90-year-old iron. The counting room is an air-conditioned Faraday cage constructed of concrete with aggregate of crystalline Precambrian limestone. We apply pulse-shape discrimination that greatly improves the precision of our 14C analyses - the reduction of background is over 70%, while the modern count rate is reduced only by 15 to 20%. The purity of the counting gas is monitored by recording the cosmic muon pulse-height spectrum. At present, the dating limit for a two-day measurement is 57 ka. We summarize here the most significant results and aspects of pulse-shape discrimination

Information

Type
I. Sample Preparation and Measurement Techniques
Information
Radiocarbon , Volume 34 , Issue 3: Proceedings of the 14th International Radiocarbon Conference , 1992, pp. 414 - 419
Copyright
Copyright © The American Journal of Science 

References

Heikkinen, A., Koivisto, A.-K. and Äikää, O. 1974 Geological Survey of Finland radiocarbon measurements VI. Radiocarbon 16(2): 252–268.Google Scholar
Kaihola, L., Kankainen, T., Mäntynen, P., Tervahauta, J. and Äikää, O. 1985 Renovation of a C-14 gas counter system. In Gulliksen, S. and Nydal, R., eds., Abstracts of the 12th International 14C Conference. Trondheim, Tapir: 3.Google Scholar
Kaihola, L., Polach, H., Kojola, H., Tervahauta, J., Mäntynen, P. and Soini, E. 1984 Low level gas multicounter for C-14 dating of small samples. In Wölfli, W., Polach, H. A. and Anderson, H. H., eds., Proceedings of the 3rd International Symposium on Accelerator Mass Spectrometry. Nuclear Instruments and Methods B5: 436–438.CrossRefGoogle Scholar
Mäntynen, P., Äikää, O., Kankainen, T. and Kaihola, L. 1987 Application of pulse-shape-discrimination to improve the precision of the carbon-14 gas-proportional-counting method. Applied Radiation Isotopes 38(10): 869–873.Google Scholar
Polach, H. A. 1987 Perspectives in radiocarbon dating by radiometry. In Gove, H. E., Litherland, A. E. and Elmore, D., eds., Abstracts of the 4th International Symposium on Accelerator Mass Spectrometry. Nuclear Instruments and Methods B29: 415–423.Google Scholar