The Brazilian AMS Radiocarbon Laboratory (LAC-UFF) and the Intercomparison of Results with CENA and UGAMS

After 22 yr of the low-level liquid scintillation counting 14C laboratory at the Center for Nuclear Energy in Agriculture (CENA) at São Paulo University (USP), Piracicaba, Brazil, and several collaborative projects with Brazilian and international researchers from distinct scientific areas, the first 14C accelerator mass spectrometry (AMS) laboratory in Latin America was installed at the Physics Institute of the Universidade Federal Fluminense (UFF), Niterói, Brazil. A 250kV single stage accelerator produced by National Electrostatics Corporation began its operation in 2012. In this work, we compare measurements performed at the AMS Radiocarbon Laboratory at UFF (LAC-UFF) with those performed at CENA and the University of Georgia (UGAMS), Georgia, USA. All the results obtained from distinct inorganic and organic samples were in very good agreement.

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Department of Earth Sciences at the University of Rome Radiocarbon Dates II

Radiocarbon ◽

10.1017/s0033822200014375 ◽

1994 ◽

Vol 36 (1) ◽

pp. 133-142

Author(s):

Gilberto Calderoni

Keyword(s):

Liquid Scintillation Counting ◽

Environmental Samples ◽

Liquid Scintillation ◽

Adriatic Sea ◽

Northern Italy ◽

Scintillation Counting ◽

National Council ◽

Radiocarbon Dates ◽

University Of Rome ◽

The University

This paper includes 14C measurements of geological and environmental samples processed by liquid scintillation counting of benzene between 1991 and the end of 1992. All samples, from central and northern Italy and from the Gulf of Venice, Adriatic Sea, relate to scientific projects conducted in collaboration with colleagues from both Italian universities and National Council of Research (CNR) institutions.

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A Review of the Radiocarbon Dates for the Afanasyevo Culture (Central Asia): Shifting Towards the “Shorter” Chronology

Radiocarbon ◽

10.1017/rdc.2018.70 ◽

2018 ◽

Vol 61 (1) ◽

pp. 243-263 ◽

Cited By ~ 3

Author(s):

Andrey V Poliakov ◽

Svetlana V Svyatko ◽

Nadezhda F Stepanova

Keyword(s):

Mass Spectrometry ◽

Accelerator Mass Spectrometry ◽

Liquid Scintillation Counting ◽

Liquid Scintillation ◽

Scintillation Counting ◽

Radiocarbon Dates ◽

Archaeological Data ◽

Depth Analysis ◽

Over Time ◽

Ams Dates

ABSTRACTThis article provides a summary and in-depth analysis of all existing radiocarbon (14C) dates for the Afanasyevo Culture of the Paleometal period. The previous “long” chronology of the culture was widely criticized and contradicted many archaeological observations. The exceedingly wide ranges of the liquid scintillation counting (LSC) dates from bone samples produced in several laboratories and the systematically older ages for the wood/charcoal samples finally reveal the shortcomings of the conventional “long” chronology. From accelerator mass spectrometry (AMS), the Afanasyevo burials of the Altai are dated to the 31st–29th century BC, whereas those of the Middle Yenisei Region to the 29th–25th century BC, which confirms the relatively earlier age of the Altai monuments. The “short” chronology removes the incompatibility of deriving the Afanasyevo Culture from the Yamnaya Culture, which previously appeared “younger” than the Afanasyevo, and also contradictions with the archaeological data. It also explains the small number of sites, the small size of the cemeteries and the lack of the internal periodization. We can now clearly move, from the earlier understanding that the Afanasyevo chronology is too broad, towards a different perception. The new AMS dates only represent a “core” for the Afanasyevo chronology, which cannot be narrowed down, but could be slightly expanded over time.

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Comparison of 14C Ages Between LSC and AMS Measurements of Choukai Jindai Cedar Tree Rings at 2600 cal BP

Radiocarbon ◽

10.1017/s0033822200045987 ◽

2010 ◽

Vol 52 (3) ◽

pp. 895-900 ◽

Cited By ~ 5

Author(s):

Yui Takahashi ◽

Hirohisa Sakurai ◽

Kayo Suzuki ◽

Taiichi Sato ◽

Shuichi Gunji ◽

...

Keyword(s):

Mass Spectrometry ◽

Tree Rings ◽

Liquid Scintillation ◽

Measurement Methods ◽

Scintillation Counting ◽

Age Difference ◽

Data Sets ◽

Data Set ◽

The Difference ◽

Good Agreement

Radiocarbon ages of Choukai Jindai cedar tree rings growing in the excess era of 14C concentrations during 2757–2437 cal BP were measured using 2 types of 14C measurement methods, i.e. liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS). The difference between the 2 methods is 3.7 ± 5.2 14C yr on average for 61 single-year tree rings, indicating good agreement between the methods. The Choukai data sets show a small sharp bump with an average 14C age of 2497.1 ± 3.0 14C yr BP during 2650–2600 cal BP. Although the profile of the Choukai LSC data set compares well with that of IntCal04, having a 14C age difference of 4.6 ± 5.3 14C yr on average, the Choukai LSC 14C ages indicate variability against the smoothed profile of IntCal04.

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University of Granada Radiocarbon Dates V

Radiocarbon ◽

10.1017/s0033822200040388 ◽

1991 ◽

Vol 33 (3) ◽

pp. 367-373 ◽

Cited By ~ 3

Author(s):

Cecilio Gonzalez-Gomez ◽

Purificacion Sanchez-Sanchez

Keyword(s):

Liquid Scintillation Counting ◽

Radiocarbon Dating ◽

Liquid Scintillation ◽

Scintillation Counting ◽

Boiling Temperature ◽

Liquid Scintillation Spectrometer ◽

Radiocarbon Dates ◽

Standard Acid ◽

Basic Procedure ◽

The University

This paper includes some determinations of archaeological, art and palaeobotanical samples from Spain and Portugal, obtained at the University of Granada Radiocarbon Dating Laboratory, mostly from 1986 to 1988. Pretreatment of charcoal and wood samples is a standard acid-basic procedure using 8% HC1 and 2% NaOH at boiling temperature. The collagen of bone samples is obtained by the Longin (1971) method.The method of dating is benzene synthesis and liquid scintillation counting as previously reported (González-Gómez, López-González & Domingo-García 1982; González-Gómez, Sánchez-Sánchez and Domingo-García 1985; González-Gómez, Sánchez-Sánchez and Villafranca-Sánchez 1986, 1987).14C activity was measured in a Packard Tri-Carb Mod 4640 liquid scintillation spectrometer, using 20 ml low 40K counting vials with 5 ml benzene and 10 ml PPO-toluene as scintillator with a background of ca. 9 cpm. Efficiency was approximately 70% using the part of spectrum above the end point of tritium.

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University of Granada Radiocarbon Dates VIII

Radiocarbon ◽

10.1017/s0033822200053285 ◽

1997 ◽

Vol 39 (3) ◽

pp. 299-303

Author(s):

Cecilio González-Gómez ◽

Elena Villafranca-Sánchez

Keyword(s):

Liquid Scintillation Counting ◽

Radiocarbon Dating ◽

Liquid Scintillation ◽

Scintillation Counting ◽

Boiling Temperature ◽

Radiocarbon Dates ◽

Standard Acid ◽

Basic Procedure ◽

The University

This paper includes determinations of archaeological, geological and paleobotanical samples from Spain and Brazil, measured at the University of Granada Radiocarbon Dating Laboratory, mainly from 1991 to 1992. As previously reported (González-Gómez 1992), pretreatment of charcoal and wood samples is a standard acid-basic procedure using 8% HCl and 2% NaOH at boiling temperature. The collagen of bone samples was extracted by the Longin (1971) method. The method of dating is liquid scintillation counting of synthesized benzene.

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University of Texas Radiocarbon Dates II

Radiocarbon ◽

10.1017/s0033822200010614 ◽

1964 ◽

Vol 6 ◽

pp. 138-159 ◽

Cited By ~ 20

Author(s):

M. A. Tamers ◽

F. J. Pearson ◽

E. Mott Davis

Keyword(s):

Chemical Synthesis ◽

Liquid Scintillation Counting ◽

Radiocarbon Dating ◽

Liquid Scintillation ◽

Scintillation Counting ◽

Radiocarbon Dates ◽

University Of Texas ◽

The University

The Radiocarbon Dating Laboratory of the University of Texas was reorganized in late 1962. The dates reported in this list were obtained from February to November, 1963. The laboratory uses liquid scintillation counting with benzene solutions (Tamers, Stipp, and Collier, 1961; Noakeset al., 1963). The chemical synthesis has been modified and improved in several ways in order to permit one worker to produce a sample per day.

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New Possibilities for 14C Measurements by Liquid Scintillation Counting

Radiocarbon ◽

10.1017/s0033822200011954 ◽

1989 ◽

Vol 31 (03) ◽

pp. 387-392 ◽

Cited By ~ 6

Author(s):

Ramon Aravena ◽

Robert R Drimmie ◽

Riffat M Qureshi ◽

Roger McNeely ◽

Sandy Fabris

Keyword(s):

Carbon Content ◽

Liquid Scintillation Counting ◽

Liquid Scintillation ◽

Standard Sample ◽

Scintillation Counting ◽

Small Samples ◽

Low Carbon ◽

Direct Absorption ◽

Organic Solution ◽

Good Agreement

Results of intercomparison tests are presented on samples analyzed using gas and liquid scintillation techniques to study the capability of the LKB Quantulus to count an organic solution used for direct absorption of CO2 and samples with low carbon content. Good agreement was obtained for small samples compared to standard sample size and for the direct absorption compared with the traditional techniques.

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Measuring 14C Concentration in Wine to Monitor Global Distribution of 14C

Radiocarbon ◽

10.1017/s0033822200048736 ◽

2013 ◽

Vol 55 (3) ◽

pp. 1827-1833

Author(s):

Hirohisa Sakurai ◽

Saori Namai ◽

Emiko Inui ◽

Fuyuki Tokanai ◽

Kazuhiro Kato ◽

...

Keyword(s):

Mass Spectrometry ◽

Correlation Coefficient ◽

Southern Hemisphere ◽

Northern Hemisphere ◽

Accelerator Mass Spectrometry ◽

Liquid Scintillation Counting ◽

Liquid Scintillation ◽

Fossil Fuel ◽

Scintillation Counting ◽

Northern And Southern Hemispheres

Using liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS), radiocarbon concentrations were measured for wine from 8 wineries located in 7 countries in the Northern and Southern hemispheres. The 14C concentrations of ethanol and residual materials in the wine were correlated (correlation coefficient 0.82). The δ14C measurements of wine samples from the mid-latitudes in the Northern Hemisphere were approximately 1l% lower than the extrapolations from Schauinsland data, suggesting a local fossil fuel effect. δ14C measurements from the wine samples from the Southern Hemisphere were higher than those from the Northern Hemisphere. The offsets of the 4 wine δ14C measurements were significant, with values between approximately 8% and 15%. Because the harvest years of the mixed grapes were estimated to be 7–12 yr older than their vintage years, this leads to a caveat when determining the 14C concentrations of the year using the wine vintage.

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Comparative Dendrochronological and14C Dating of 15th Century Russian Icon

Radiocarbon ◽

10.2458/azu_rc.57.17467 ◽

2015 ◽

Vol 57 (1) ◽

pp. 173-182 ◽

Cited By ~ 5

Author(s):

Konstantin Voronin ◽

Andrey Dolgikh ◽

Vladimir Matskovsky ◽

Alexander Cherkinsky ◽

Vadim Skripkin ◽

...

Keyword(s):

Mass Spectrometry ◽

Calibration Curve ◽

Liquid Scintillation Counting ◽

Liquid Scintillation ◽

Fine Art ◽

Scintillation Counting ◽

13Th Century ◽

15Th Century ◽

Complete Tree ◽

Ams Dates

A 15th century Russian icon from the Novgorod region was analyzed using both dendrochronological and radiocarbon methods [liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS)]. This orthodox icon represents the Mother of God (Dexiokratusa). Fine art experts attribute the icon to between the late 14th to the early 15th centuries. The last complete tree ring was dated to AD 1409. There are indications that the trees were cut down during the summer of AD 1410. Taking into account the time for seasoning (about 8 months), the icon would have been painted in AD 1411. Wiggle-matching of the six AMS samples failed. Two of six AMS dates correspond to dendrochronological dates, while four of the six AMS dates showed differences with the dendrochronological dates by 5–39 yr. This discrepancy raises the issue of a possible regional offset from the calibration curve for the 13th century AD in NW Russia.

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University of Barcelona Radiocarbon Dates I

Radiocarbon ◽

10.1017/s0033822200040376 ◽

1991 ◽

Vol 33 (3) ◽

pp. 355-365

Author(s):

J. S. Mestres ◽

Gemma Rauret ◽

J. F. Garcia

Keyword(s):

Measurement Technique ◽

Liquid Scintillation Counting ◽

Liquid Scintillation ◽

Sample Pretreatment ◽

Scintillation Counting ◽

Geological Samples ◽

Radiocarbon Dates ◽

The University ◽

Serial Measurements

The Radiocarbon Laboratory at the University of Barcelona began its serial measurements in 1985. The following list contains dates obtained between 1985 and 1987. Both archaeological and geological samples were dated.The measurement technique we use is liquid scintillation counting of benzene. A previous paper (Mestres, García & Rauret 1991) describes sample pretreatment, synthesis and counting protocols and equipment.

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