14C Dating with the Gif-sur-Yvette Tandetron Accelerator: Status Report and Study of Isotopic Fractionation in the Sputter Ion Source

The standard procedure for measuring 14C at the Gif-sur-Yvette Tandetron AMS facility is described. A new sample manipulator and automated measurements are being used and have been operational for six months. Evidence of isotopic fractionation in the sputter ion source is provided. We take this into account by measuring the 13C/12C ratio of the sample in the accelerator.

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Untersuchung von Calciumisotopieeffekten bei heterogenen Austauschgleichgewichten / Investigation of Isotopic Effects of Calcium in Heterogeneous Exchange Equilibria

Zeitschrift für Naturforschung B ◽

10.1515/znb-1972-0204 ◽

1972 ◽

Vol 27 (2) ◽

pp. 126-133 ◽

Cited By ~ 33

Author(s):

Klaus Gustav Heumann ◽

Karl Heinrich Lieser

Keyword(s):

Separation Factor ◽

Calcium Concentration ◽

Isotopic Fractionation ◽

Ion Source ◽

Isotopic Effect ◽

Mass Unit ◽

Calcium Isotopes ◽

Heterogeneous Exchange ◽

Loaded Column ◽

Isotopic Effects

The following heterogeneous exchange equilibria have been examined for isotopic effects: CaCO3/Ca(aq.)2⊕. Ca-GBHA/Ca(aq.)2⊕ and Ca(Dowex 50)2⊕/Ca(aq.)2⊕ (GBHA = glyoxal-bis (2-hydroxyanil)). The isotopic ratios 44Ca/40Ca and 48Ca/40Ca were determined by means of a mass spectrometer with a thermal ion source. In the system CaCO3/Ca(aq.)2⊕, the elementary separation factor was found to be less than 1‰ or 0,5‰ per mass unit, respectively.For the exchange in the system Ca-GBHA/Ca(aq.)2⊕ in the concentration range from 0.011 to 0.84 M an elementary separation factor less than 1‰ per mass unit was found; from a three-stage experiment at a calcium concentration of 1.23 M it was concluded that the elementary isotopic effect is less than 0.4‰ per mass unit. Therefore no isotopic fractionation is to be expected for precipitation of inorganic or organic calcium salts.An enrichment of the heavier calcium isotopes in the solution was found in the case of the exchange in a Dowex 50-X12 loaded column. The isotopic effect depends on the concentration of the hydrochloric acid used as the eluent.

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14C-Dating of the Late Bronze Age City of Hala Sultan Tekke, Cyprus: Status Report

Radiocarbon ◽

10.1017/rdc.2019.75 ◽

2019 ◽

Vol 61 (5) ◽

pp. 1253-1264 ◽

Cited By ~ 1

Author(s):

Eva M Wild ◽

Peter M Fischer ◽

Peter Steier ◽

Teresa Bürge

Keyword(s):

Bronze Age ◽

Status Report ◽

Late Bronze Age ◽

14C Dating ◽

Archaeological Evidence ◽

Southern Scandinavia ◽

New City ◽

The City ◽

Vast Area ◽

Existing Data

ABSTRACTHala Sultan Tekke is a large Bronze Age city located on the southeastern littoral of Cyprus. The city flourished from approximately 1650 BC to 1150 BC according to the archaeological evidence. Since 2010, Swedish excavations have exposed four new city quarters (CQ1–4) with three occupational phases, the 14C dating of which is of highest importance also for other contemporaneous cultures. The finds demonstrate vast intercultural connections in the Mediterranean and even with southern Scandinavia. In 2014, roughly 500 m to the east of CQ1, one of the richest cemeteries on the island was discovered. According to the archaeological evidence, the finds from the city date mainly to the 13th and 12th centuries BC. However, many of the wealthy tombs and the offering pits from the cemetery are considerably older with the oldest finds dating to the 16th century BC. This raises the question where the city quarters belonging to the oldest finds from the cemetery are situated. The radiocarbon (14C) dates from Hala Sultan Tekke have much influence on the dating of related sites because of numerous imports from a vast area. We present here new 14C data obtained in the course of the current excavations, which add to sets of already existing data.

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Status report of the 28GHz superconducting electron cyclotron resonance ion source VENUS (invited)

Review of Scientific Instruments ◽

10.1063/1.2149298 ◽

2006 ◽

Vol 77 (3) ◽

pp. 03A302 ◽

Cited By ~ 40

Author(s):

D. Leitner ◽

C. M. Lyneis ◽

T. Loew ◽

D. S. Todd ◽

S. Virostek ◽

...

Keyword(s):

Cyclotron Resonance ◽

Electron Cyclotron Resonance ◽

Ion Source ◽

Electron Cyclotron ◽

Status Report

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Status report on ECR ion source operation at GANIL

Review of Scientific Instruments ◽

10.1063/1.1690447 ◽

2004 ◽

Vol 75 (5) ◽

pp. 1488-1491 ◽

Cited By ~ 4

Author(s):

P. Lehérissier ◽

C. Barué ◽

C. Canet ◽

M. Dubois ◽

M. Dupuis ◽

...

Keyword(s):

Ion Source ◽

Status Report ◽

Ecr Ion Source ◽

Source Operation

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Miniature radiocarbon measurements ( < 150 µg C) from sediments of Lake Żabińskie, Poland: effect of precision and dating density on age–depth models

Geochronology ◽

10.5194/gchron-2-63-2020 ◽

2020 ◽

Vol 2 (1) ◽

pp. 63-79 ◽

Cited By ~ 1

Author(s):

Paul D. Zander ◽

Sönke Szidat ◽

Darrell S. Kaufman ◽

Maurycy Żarczyński ◽

Anna I. Poraj-Górska ◽

...

Keyword(s):

Lacustrine Sediments ◽

Plant Macrofossils ◽

Ion Source ◽

14C Dating ◽

Sample Mass ◽

Carbon Dating ◽

Analytical Precision ◽

Ne Poland ◽

Gas Source

Abstract. The recent development of the MIni CArbon DAting System (MICADAS) allows researchers to obtain radiocarbon (14C) ages from a variety of samples with miniature amounts of carbon (<150 µg C) by using a gas ion source input that bypasses the graphitization step used for conventional 14C dating with accelerator mass spectrometry (AMS). The ability to measure smaller samples, at reduced cost compared with graphitized samples, allows for greater dating density of sediments with low macrofossil concentrations. In this study, we use a section of varved sediments from Lake Żabińskie, NE Poland, as a case study to assess the usefulness of miniature samples from terrestrial plant macrofossils for dating lake sediments. Radiocarbon samples analyzed using gas-source techniques were measured from the same depths as larger graphitized samples to compare the reliability and precision of the two techniques directly. We find that the analytical precision of gas-source measurements decreases as sample mass decreases but is comparable with graphitized samples of a similar size (approximately 150 µg C). For samples larger than 40 µg C and younger than 6000 BP, the uncalibrated 1σ age uncertainty is consistently less than 150 years (±0.010 F14C). The reliability of 14C ages from both techniques is assessed via comparison with a best-age estimate for the sediment sequence, which is the result of an OxCal V sequence that integrates varve counts with 14C ages. No bias is evident in the ages produced by either gas-source input or graphitization. None of the 14C ages in our dataset are clear outliers; the 95 % confidence intervals of all 48 calibrated 14C ages overlap with the median best-age estimate. The effects of sample mass (which defines the expected analytical age uncertainty) and dating density on age–depth models are evaluated via simulated sets of 14C ages that are used as inputs for OxCal P-sequence age–depth models. Nine different sampling scenarios were simulated in which the mass of 14C samples and the number of samples were manipulated. The simulated age–depth models suggest that the lower analytical precision associated with miniature samples can be compensated for by increased dating density. The data presented in this paper can improve sampling strategies and can inform expectations of age uncertainty from miniature radiocarbon samples as well as age–depth model outcomes for lacustrine sediments.

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Status report on the Stockholm cryogenic electron beam ion source

10.1063/1.38397 ◽

1989 ◽

Cited By ~ 2

Author(s):

L. Liljeby ◽

Ȧ. Engström

Keyword(s):

Electron Beam ◽

Ion Source ◽

Status Report

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Capabilities of the New SUERC 5MV AMS Facility for 14C Dating

Radiocarbon ◽

10.1017/s0033822200039357 ◽

2004 ◽

Vol 46 (1) ◽

pp. 59-64 ◽

Cited By ~ 75

Author(s):

S Xu ◽

R Anderson ◽

C Bryant ◽

G T Cook ◽

A Dougans ◽

...

Keyword(s):

Ion Source ◽

Negative Ion ◽

Environmental Research ◽

Research Centre ◽

Performance Tests ◽

14C Dating ◽

Routine Measurement ◽

Consensus Values ◽

Accelerator Mass Spectrometer ◽

Routine Basis

A new National Electrostatic Corporation (NEC) 5MV accelerator mass spectrometer became operational at the Scottish Universities Environmental Research Centre (SUERC) in July 2002. It has 2 Cs sputter negative ion sources: a 134-sample source (S1) for the routine measurement of all species, and a hybrid source (S2) with 40 spaces for radiocarbon measurements with either graphite or CO2 samples. A number of performance tests on graphite samples have been carried out on both sources. A precison of better than 0.3% is feasible for modern samples on a routine basis. The 14C background of the machine and the graphite preparation process blank are 0.04 ± 0.01 and 0.16 ± 0.05 pMC, respectively, indicating that 14C dating back to ~50 kyr BP is possible. The normalized 14C values for a series of reference materials agree well with the IAEA, TIRI, and FIRI consensus values. Routine measurement of 14C has been underway since May 2003. Preliminary results of performance tests on the CO2 gas ion source are also reported.

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