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Review of the Scientific Approaches Used During the FBI's Investigation of the 2001 Anthrax Letters (2011) / Chapter Skim
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Appendix A: Radiocarbon Dating
Pages 181-182

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From page 181...
... and the solar activity that is a dominant source of the earth's cosmic rays. Tree rings and corals have been used as calibrations to relate the ∆14C to actual calendar ages.
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From page 182...
... The rise from values near zero bitmap results from atmospheric testing of nuclear weapons. The decline from peak values reached in late 1963 results from the exchange of CO2 between the atmosphere and ocean.
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Key Terms

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  • actual calendar
  • advanced tremendously
  • ratios correspond
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  • tree rings

  • using data
  • calendar ages
  • cosmic rays
  • mass spectrometry
  • radioactive decay

  • atoms decay
  • animal dies
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  • atmospheric nuclear
  • curve using


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