Radiocarbon accelerator

E. Wild, R. Golser, P. Hille, W. Kutschera, A. Priller, S. Puchegger, W. Rom, P. Steier and W. Vycudilik, First 14C results from archaeological and forensic studies at the Vienna Environmental Research Accelerator, Radiocarbon 40, 273 281 (1998). 

Gillespie, R., Hedges, R.E.M. and Wand, J.O. 1984 Radiocarbon dating of bone by Accelerator Mass Spectrometry. Journal of Archaeological Science 11 165-170. 

Soon after this discovery the harnessing of the technique to the measurement of all the U isotopes and all the Th isotopes with great precision immediately opened up the entire field of uranium and thorium decay chain studies. This area of study was formerly the poaching ground for radioactive measurements alone but now became part of the wonderful world of mass spectrometric measurements. (The same transformation took place for radiocarbon from the various radioactive counting schemes to accelerator mass spectrometry.)... 

A more recently developed technique, known as the accelerator mass spectrometry (AMS) radiocarbon dating technique, based on counting, in a mass spectrometer, the relative amount of radiocarbon to stable carbon isotopes in a sample (see Textbox 10). 

AMS 14C dating Abbreviation for accelerator mass spectrometry radiocarbon dating. AMU Acronym for atomic mass unit. 

Harris, D. R. (1987), The impact on archaeology of radiocarbon dating by accelerator mass spectrometry, Phil. Trans. Roy. Soc. A323, 23-43. 

Valladas, H. (2003), Direct radiocarbon dating of prehistoric cave paintings by accelerator mass spectrometry, Meas. Sci. Technol. 14, 1487-1492. 

The impact of this new technique, which was called Accelerator Mass Spectrometry (AMS), on the radiocarbon and archaeologist communities, was immediate and revolutionary. The introduction of AMS is indeed recognized by some as the third revolution in radiocarbon dating[22,23] and it has provided the opportunity to date very precious finds by collecting very small samples. The interest in developing the technique of AMS was so evident that, just few years after the measurements cited above, a first dedicated AMS system (based on a tandem accelerator) was designed and built [24] then, the first dedicated... 

However, the most significant development in recent years has been represented by the trend towards smaller facilities based on smaller accelerators. The work done at ETH in Zurich on the study of stripping yields, molecular dissociation and detection efficiency at low energies has led to the development of systems based on low voltage tandem machines they have demonstrated that 14C measurement is also possible using 500 kV or even 200 kV accelerators.[61,62] The main advantage in the use of dedicated 14C smaller accelerators is the reduced space requirements [63] for example, while the 3 MV VERA facility covers an area of 192 m2, the compact 500 kV AMS system at the Poznan Radiocarbon Laboratory in Poland covers an area of 30 m2 and the 200 kV MICADAS system in Zurich only about 7 m2. 

K.H. Purser, R.B. Liebert and C.J. Russo, MACS an accelerator based radioisotope measuring system, Radiocarbon 22, 794 806 (1980). 

A. E. Litherland and L. R. Kilius, A recombinator for radiocarbon accelerator mass spectrometry, Nucl. Instrum. Methods B 52, 375 377 (1990). 

Proc. First Conference on Radiocarbon Dating with Accelerators, ed. H. E. Gove, Rochester, 1978. 

Our project to test a Tandem accelerator for multi-beam detection was then to modify the accelerator analyzing magnet such that the various beams could be dispersed and detected simultaneously, to design an injection system to appropriately process the different isotopic beams from the ion source for injection into the accelerator, and to construct an ion-source to allow us to routinely handle small samples. Our interests at present lie in radiocarbon and radioberyllium studies, and so we have designed this system to accommodate these isotopes. 

Sample Preparation for Electrostatic Accelerator Dating of Radiocarbon... 

Graphite produces the large beam currents desirable in electrostatic accelerator dating of radiocarbon. However, samples to be dated can be converted to other forms of carbon with less effort, and still provide satisfactory results. 

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