scholarly journals Teledyne Isotopes Radiocarbon Measurements XII

Radiocarbon ◽  
1981 ◽  
Vol 23 (3) ◽  
pp. 329-344 ◽  
Author(s):  
James Buckley ◽  
Cynthia Valdes-Pages
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Half Life ◽  
Counting Statistics ◽  
Modern Standard

This date list reports samples completed before 1979. Methods, equipment, and techniques were reported previously (R, 1968, v 10, p 246; R, 1970, v 12, p 87). Age calculations are based on the conventional 14C half-life of 5568 years. The working laboratory standard is 95% of the NBS oxalic acid standard (SRM 4990). Results are reported in years before 1950 and the standard deviation is based on counting statistics of sample, background, and modern standard. Corrections for δ13C are not included.

scholarly journals Physical Research Laboratory Radiocarbon Date List VI

Radiocarbon ◽  
1991 ◽  
Vol 33 (3) ◽  
pp. 329-344 ◽  
Author(s):  
D. P. Agrawal ◽  
Sheela Kusumgar ◽  
M. G. Yadava
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Proportional Counter ◽  
Research Laboratory ◽  
Radiocarbon Date ◽  
Geological Samples ◽  
Physical Research Laboratory ◽  
Detailed Procedure ◽  
Counting Statistics ◽  
Modern Standard

We present here dates for archaeological and geological samples. The dates are based on τ1/2 = 5568 years, using 1950 as the base year. The modern standard was 95% of activity of NBS oxalic acid.Samples were pretreated, prepared by methane synthesis and counted in a proportional counter. The detailed procedure has been described earlier (Agrawal, Gupta & Kusumgar 1971). We reported minor changes in previous date lists. Quoted errors are based on counting statistics alone. For samples younger than 10,000 years, the error is 1 standard deviation, and for older samples, 2 standard deviations. The dates are not corrected for 13C fractionation. Samples have been arranged alphabetically according to the name of the site.

scholarly journals Tartu Radiocarbon Dates XIII

Radiocarbon ◽  
1994 ◽  
Vol 36 (1) ◽  
pp. 153-158
Author(s):  
Arvi Liiva ◽  
Ilze Loze
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Liquid Scintillation Counting ◽  
Half Life ◽  
Liquid Scintillation ◽  
Standard Sample ◽  
Scintillation Counting ◽  
Radiocarbon Dates ◽  
Academy Of Sciences ◽  
Modern Standard

This date list reports dates of archaeological samples of Mesolithic and Neolithic sites of Estonia, Latvia and Lithuania. We use liquid scintillation counting at the Geochemical and Statistical Laboratory of the Institute of Zoology and Botany, Estonian Academy of Sciences. Our modern standard is benzene enriched in 14C and its activity is checked with an NBS oxalic acid standard sample. Dates are given in conventional 14C years, based on the Libby half-life of 5570 ± 30 yr. AD 1950 is the reference year. Errors are based on one standard deviation calculated from count rates.

scholarly journals National Taiwan University Radiocarbon Measurements II

Radiocarbon ◽  
1973 ◽  
Vol 15 (2) ◽  
pp. 345-349 ◽  
Author(s):  
Yuin-Chi Hsu ◽  
Muh-Chen Chou ◽  
Yi-Chuan Hsu ◽  
Song-Yun Lin ◽  
Shih-Chong Lu
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Proportional Counter ◽  
Half Life ◽  
Statistical Nature ◽  
Radiocarbon Dates ◽  
Disintegration Process ◽  
Modern Standard

The C14 dates given below have been obtained by counting CO2 at 2 atm pressure in a 1 L proportional counter. Details of procedure are given in our previous list (R., 1970, v. 12, p. 187–192). Radiocarbon dates in this list are based on 95% of activity of NBS oxalic acid as the modern standard and were calculated using 5570 yr as the half-life of C14. Errors quoted with the dates are standard deviation originating from the statistical nature of radioactive disintegration process. Results obtained during 1970 and 1971 are described here.

scholarly journals Gif Natural Radiocarbon Measurements IX

Radiocarbon ◽  
1982 ◽  
Vol 24 (3) ◽  
pp. 291-343 ◽  
Author(s):  
Georgette Delibrias ◽  
Marie-Thérèse Guillier ◽  
Jacques Labeyrie
Keyword(s):  
Standard Deviation ◽  
South America ◽  
Oxalic Acid ◽  
West Africa ◽  
Sea Level ◽  
Half Life ◽  
Sea Level Variations ◽  
Geologic Samples ◽  
Modern Standard

The following list includes 14C measurements of geologic samples, the majority of which pertain to sea-level variations, and of archaeologic samples mainly from France, West Africa, and South America. Most of the dates were measured between 1972 and 1973 when installations were not modified. The technique used is described in Radiocarbon, 1972, v 14, p 280–320. Dates were calculated using the 14C half-life of 5568 years; modern standard is 0.95 of the NBS oxalic acid. Reported errors are one standard deviation for 2000 minutes measurements.

scholarly journals Physical Research Laboratory Radiocarbon Date List V

Radiocarbon ◽  
1985 ◽  
Vol 27 (1) ◽  
pp. 95-110 ◽  
Author(s):  
D P Agrawal ◽  
R V Krishnamurthy ◽  
Sheela Kusumgar
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Research Laboratory ◽  
Radiocarbon Date ◽  
Physical Research Laboratory ◽  
Physical Research ◽  
Geologic Samples ◽  
Standard Deviations ◽  
Counting Statistics ◽  
Modern Standard

We report here dates on archaeologic and geologic samples. The samples were counted as methane in gas proportional counters. The techniques used have been described earlier (R, 1971, v 13, p 442–449). Dates are expressed in years BP, taking AD 1950 as the reference year. Modern standard was NBS oxalic acid. Quoted errors are based on counting statistics alone and are equivalent to ±1 standard deviation for samples younger than 10,000 years and ± 2 standard deviations for older samples. Descriptions and references regarding the samples have been supplied by the submitters of the samples.

scholarly journals Tartu Radiocarbon Dates XI

Radiocarbon ◽  
1990 ◽  
Vol 32 (1) ◽  
pp. 99-105 ◽  
Author(s):  
Evald Ilves
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Half Life ◽  
Liquid Scintillation ◽  
Standard Sample ◽  
Single Channel ◽  
Radiocarbon Dates ◽  
Geologic Samples ◽  
Modern Standard

This list includes dates of geologic samples measured using a single-channel liquid scintillation 14C counter at the Geochemical and Statistical Laboratory, Tartu, Estonian SSR. Our modern standard is made of benzene enriched in 14C and its activity is checked with NBS oxalic acid standard sample. Dates are given in conventional radiocarbon years, based on the Libby half-life of 5570 ± 30 yr. AD 1950 is the reference year. Errors refer only to 1σ standard deviation calculated from count rates involved.

scholarly journals Quebec Radiocarbon Measurements III

Radiocarbon ◽  
1981 ◽  
Vol 23 (2) ◽  
pp. 241-251 ◽  
Author(s):  
Louis Barrette ◽  
Pierre La Salle ◽  
Claude Samson
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Liquid Scintillation Counting ◽  
Half Life ◽  
Liquid Scintillation ◽  
Scintillation Counting ◽  
The Given ◽  
Deviation Criterion ◽  
Modern Standard

The results presented in this list have been obtained by benzene synthesis and liquid scintillation counting: ages are calculated using the 14C half-life of 5570 yr with 0.95 activity of NBS oxalic acid as modern standard, with no correction. The given precision is obtained from a one-standard-deviation criterion.

scholarly journals Tartu Radiocarbon Dates XII

Radiocarbon ◽  
1991 ◽  
Vol 33 (3) ◽  
pp. 345-354
Author(s):  
Evald Ilves
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Half Life ◽  
Liquid Scintillation ◽  
Standard Sample ◽  
Single Channel ◽  
Geological Samples ◽  
Radiocarbon Dates ◽  
Modern Standard

IntroductionThis list includes dates of geological samples measured using a single-channel liquid scintillation 14C counter at the Geochemical and Statistical Laboratory, Tartu, Estonia. Our modern standard is made of benzene enriched in 14C, and its activity is checked with NBS oxalic acid standard sample. Dates are given in conventional radiocarbon years, based on the Libby half-life of 5570 ± 30 years. A.D. 1950 is the reference year. Errors refer only to 1σ standard deviation calculated from count rates involved.

scholarly journals University of Lund Radiocarbon Dates XVII

Radiocarbon ◽  
1984 ◽  
Vol 26 (3) ◽  
pp. 392-411 ◽  
Author(s):  
Sören Håkansson
Keyword(s):  
Standard Deviation ◽  
Oxalic Acid ◽  
Half Life ◽  
Radiocarbon Dates ◽  
Counting Statistics

Most of the 14C measurements reported here were made between October 1982 and October 1983. Equipment, measurement, and treatment of samples are as reported previously (R, 1968, v 10, p 36–37; 1976, v 18, p 290; 1980, v 22, p 1045).Age calculations are based on a contemporary value equal to 95% of the activity of NBS oxalic acid standard (No. 4990A) and on the conventional half-life for 14C of 5568 yr. Results are reported in years before 1950 (years bp). Errors quoted with the dates are based on counting statistics alone and are equivalent to ± 1 standard deviation (±σ).

scholarly journals University of Texas Radiocarbon Dates III

Radiocarbon ◽  
1965 ◽  
Vol 7 ◽  
pp. 296-314 ◽  
Author(s):  
F. J. Pearson ◽  
E. Mott Davis ◽  
M. A. Tamers ◽  
Robert W. Johnstone
Keyword(s):  
Oxalic Acid ◽  
Half Life ◽  
Radiocarbon Dates ◽  
University Of Texas ◽  
Sample Count ◽  
Counting Statistics ◽  
Modern Standard

This list reports measurements made at this laboratory since the preparation of the last list (Texas II). About twenty measurements are not reported because they are from series which are incomplete. Ages were calculated using a C14 half-life of 5568 yr and 1950 as the reference year. The modern standard used was 95% of NBS oxalic acid activity. The deviations reported are based on the counting statistics of the sample, background, and modern, and are ±1σ except that when the sample count approached either the modern standard or the background, 2σ limits are reported.

Sign in / Sign up

Export Citation Format

Share Document