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7555689 
Journal Article 
Measurement of low C-14 activities in a liquid scintillation counter in the Zagreb Radiocarbon Laboratory 
Horvatincic, N; Baresic, J; Bronic, IK; Obelic, B 
2004 
1 
Radiocarbon
ISSN: 0033-8222 
UNIV ARIZONA DEPT GEOSCIENCES 
TUCSON 
46 
1 
105-116 
WOS:000223194200015 
Two methods of chemical preparation of radiocarbon samples are implemented in the Zagreb Radiocarbon Laboratory for measurement by a new liquid scintillation counter (LSC), Quantulus 1220(TM) : a CO2 absorption method (LSC-A) and a benzene synthesis method (LSC-B). For samples prepared by both methods, the optimal counting windows for measurement in LSC were determined. The total efficiency of LSC-A is 65% and that of the LSC-B is 83%, while the corresponding C-14 dating limits are 31,800 yr and 52,160 yr, respectively. C-14 activities measured by the LSC-A and LSC-B methods were compared with those measured by the gas proportional counter (GPC) method (efficiency 75%, C-14 dating limit 37,500 yr). The results obtained by the LSC-A method have larger errors than those measured by the GPC method, but LSC-A is quick, inexpensive, simple, and requires less carbon than the GPC method. Thus, LSC-A is suitable for C-14 measurements of geological, hydrological, and environmental samples. On the other hand, the results obtained by the LSC-B method give smaller errors and a larger C-14 dating range. Therefore, LSC-B is more suitable for C-14 dating of archaeological samples. 
18th International Radiocarbon Conference 
Wellington, NEW ZEALAND