Reassessment of uncertainty expansion by linear addition of long-term components from top-down information

Salazar, G.; Szidat, S. (2021). Reassessment of uncertainty expansion by linear addition of long-term components from top-down information. Radiocarbon, 63(6), pp. 1657-1671. Cambridge University Press 10.1017/RDC.2021.96

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Since radiocarbon accelerator mass spectrometry (14C AMS) is considered a high-precision technique, reassessment of the measurement uncertainty has been a topic of interest. Scientists from analytical and metrological fields have developed the top-down and bottom-up measurement of uncertainty approaches. The 14C quoted error should approximate the uncertainty of long-term repetitions of the top-down approach in order to be realistic. The novelty of this paper is that the uncertainty of both approaches were approximated to each other. Furthermore, we apportioned the graphitization, instrumentation, and bias components in order to additively expand the quoted error. Our results are comparable to error multipliers and to long-term repeatability studies reported by other laboratories. Our laboratory was established in late 2012 with N2 as stripper gas and 7 years later, we changed to helium stripper. Thus, we were able to compare both gases, and demonstrate that helium is a better stripper gas. In absolute F14C units, the ranges of graphitization+bias combined uncertainties were (0.7 to 4.1) × 10–3 for N2 and (0.7–3.0) × 10–3 for He depending on the standard 14C content. The error multiplier for He defined as the expanded uncertainty over quoted error, in average, was 1.7; while without the bias, the multiplier was 1.3.

Item Type:

Journal Article (Original Article)


10 Strategic Research Centers > Oeschger Centre for Climate Change Research (OCCR)
08 Faculty of Science > Department of Chemistry, Biochemistry and Pharmaceutical Sciences (DCBP)

UniBE Contributor:

Salazar Quintero, Gary Abdiel, Szidat, Sönke


500 Science > 540 Chemistry




Cambridge University Press




Sönke Szidat

Date Deposited:

04 Feb 2022 10:00

Last Modified:

05 Dec 2022 16:04

Publisher DOI:





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