Radiocarbon dating using electrostatic accelerators: negative ions provide the key.
Mass spectrometric methods have long been suggested as ways of measuring (14)C/(12)C ratios for carbon dating. One problem has been to distinguish between (14)N and (14)C. With negative ions and a tandem electrostatic accelerator, the (14)N background is virtually absent and fewer than three (14)C atoms in 10(16) atoms of (12)C have been easily measured.
Bennett
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Beukens
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Clover
M R
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Gove
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Liebert
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Litherland
A E
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Purser
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Sondheim
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