Reduction in Backgrounds of Microsamples for AMS 14C Dating
Open accessAbstract
Vogel, Nelson and Southon (1987) determined that the total-system 14 C background values in catalytically reduced graphitic carbon samples of 500 mg or less were inversely proportional to their weights. We have used wood reportedly of Pliocene age (i.e., 14 C “dead”) to further examine this relation. Our observations are consistent with the conclusions of Vogel, Nelson and Southon (1987). It appears that contamination can be characterized as if a constant level of modern carbon is being added. We also report a significant overall net reduction in total system background values ca. 45% for combusted samples from levels previously reported by Vogel, Nelson and Southon (1987).
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The cause of the increasing 14C background values as a function of declining amounts of infinite age material in the synthesized graphite is very similar amounts of micro-contamination added to all synthesized graphite samples during the combustion/acidification and/or graphitization process.
“The cause of these effects has been demonstrated to be due to the very similar amounts of micro-contamination being added to all synthesized graphite samples during the combustion/acidification and/or graphitization process that we have previously described (Vogel et al. 1987;Kirner et al. 1995;Brown and Southon 1997).”
From Misunderstandings Concerning the Significance of AMS Background <sup>14</sup>C Measurements (2018) · cites this paper as Kirner et al. 1995
In “Sources and Levels of Contamination” (page not provided), the paper reports that radiocarbon background rises as graphite sample weight falls and describes a model in which a roughly constant amount of contamination is added during combustion and/or graphitization. Its conclusion says the authors’ data are *consistent with* that model, not that they demonstrated it to be the cause in all synthesized graphite samples. The citing sentence overstates the certainty and scope of the finding. (LLM, conf=0.86)
Experimental — accuracy not yet measuredAs sample sizes decrease, the effect of contaminant carbon on blanks becomes more prominent.
“As sample sizes decrease, the effect of contaminant carbon on blanks becomes more prominent (Vogel et al. 1987; Kirner et al. 1995).”
From Blank Assessment for Ultra-Small Radiocarbon Samples: Chemical Extraction and Separation Versus AMS (2010) · cites this paper as Kirner et al. 1995
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Cites
<sup>14</sup>C Background Levels in An Accelerator Mass Spectrometry System
Vogel, J. S., Nelson, D. E., & Southon, J. R. (1987) · Radiocarbon · doi:10.1017/s0033822200043733 · Cited by 286 · see citing works
Self-citation
Flagged first, then by citations
Research works printed but not linked: 8
- Beukens, R. P. 1992 Radiocarbon accelerator mass spec- trometry: Background, precision and accuracy. In Tay- lor, R. E., Long, A. and Kra, R. S., eds., Radiocarbon AfterFourDecades: An InterdisciplinaryPerspective. New York, Springer-Verlag: 230-239.
- Boutton, T. W. 1991 Stable carbon ratios of natural ma- terials: I. Sample preparation and mass spectrometric analysis. In Coleman, D. C. and Fry, B., eds., Carbon Isotope Techniques. San Diego, Academic Press, Inc.: 155-170.
- Gulliksen, S. and Thomsen, M. S. 1992 Examination of background contamination levels for gas counting and AMS target preparation in Trondheim. In Long, A. and Kra, R. S., eds., Proceedings of the 14th Interna- tional 14C Conference. Radiocarbon 34(3): 312-317.
- Gurfinkel, D. M. 1987 An assessment of laboratory con- tamination at the Isotrace Radiocarbon Facility. Ra- diocarbon 29(3): 335-346.
- Southon, J. R., Vogel, J. S., Trombone, S. E., Advise, J. C., Robbers, M. L., Cafe, M. W., Finical, R. C., Proc- tor, I. D., Heikkinen, D. W., Berno, A. J. and Hornady, R. S. 1992 Progress in AMS measurements at the https://doi.org/10.1017/S0033822200031222 Published online by Cambridge University Press
- LLNL spectrometer. In Long, A. and Kra, R. S., eds. Proceedings of the 14th International 14C Conference. Radiocarbon 34(3): 473-477.
- Taylor, R. E. 1987 Radiocarbon Dating: An Archaeolog- icaI Perspective. New York, Academic Press: 212 p. 1991 Radioisotope dating by accelerator mass spec- trometry: Archaeological and paleoanthropological perspectives. In Goksu, H. Y., Oberhofer, M. and Reg- ulloi, D., eds., Scientific Dating Methods. Dordrecht, Kluwer Academic Publishers: 37-54.
- Vogel, J. S., Nelson, D. E. and Southon, J. R.198714C background levels in an accelerator mass spectrome- try system. Radiocarbon 29(3): 323-333.
Cited by
Sorted by citations
Blank Assessment for Ultra-Small Radiocarbon Samples: Chemical Extraction and Separation Versus AMS
Santos, G. M., Southon, J. R., Drenzek, N. J., Ziolkowski, L. A., Druffel, E., Xu, X., Zhang, D., Trumbore, S., Eglinton, T. I., & Hughen, K. A. (2010) · Radiocarbon · doi:10.1017/s0033822200046415 · Cited by 103 · see citing works
Self-citationUse of natural diamonds to monitor 14C AMS instrument backgrounds
Taylor, R. E., & Southon, J. (2007) · Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms · doi:10.1016/j.nimb.2007.01.239 · Cited by 13 · see citing works
Self-citationMisunderstandings Concerning the Significance of AMS Background <sup>14</sup>C Measurements
Taylor, R. E., Southon, J. R., & Santos, G. M. (2018) · Radiocarbon · doi:10.1017/rdc.2018.15 · Cited by 3 · see citing works
Self-citation
- Authors
- Kirner, D. L., Taylor, R. E., & Southon, J. R.
- Affiliations
- University of California, Riverside (US)
- Lawrence Livermore National Laboratory (US)
- ORCID
- Southon, John R.
- Venue
- Radiocarbon
- Publisher
- Cambridge University Press (CUP)
- Published
- 1995
- Volume
- 37
- Issue
- 2
- Pages
- 697-704
- ISSN
- 0033-8222 (ISSN-L)
- 1945-5755
- OpenAlex
- W2207704907
- Cited by
- 36
- References
- 1
- Citations by year
- 2018: 1 · 2017: 1 · 2016: 2 · 2015: 1 · 2012: 1
- FWCI
- 5.69
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Radiocarbon (publishedVersion)
- UA Campus Repository (The University of Arizona) (acceptedVersion)
- Funders
- University of California
- University of California, Los Angeles
- College of Humanities and Social Sciences, United Arab Emirates University
- Lawrence Livermore National Laboratory
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Archaeology and ancient environmental studies
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
- Physical Sciences › Physics and Astronomy › Radiation › Radioactive Decay and Measurement Techniques
- Keywords
- microsamples, dead wood, contamination, graphitic carbon
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